D600014 Multifunction Power System

Product Information: Multifunction Power System (Cat C1.1

Engine ECU Equipped)

Specifications

• Model: Multifunction Power System (Cat MF)
• Engine: Cat C1.1 engine (ECU Equipped)
• Part Number: D600014

Product Usage Instructions

1. Installation

To install the Multifunction Power System, please follow the
steps below:

1. Refer to the Multifunction Power System (Cat) Installation
   Manual for detailed installation instructions.

2. Ensure that you have all the necessary tools and equipment
   before starting the installation.

3. Follow the recommended safety precautions mentioned in the
   Safety section of this manual.

4. Connect the Multifunction Power System to the Cat C1.1 engine
   using the provided connectors.

5. Securely mount the system in the desired location on your
   vehicle.

6. Refer to the installation manual for any additional steps
   specific to your vehicle or application.

2. Owner’s Manual

The Multifunction Power System Owner’s Manual provides important
information regarding the operation and maintenance of the system.
It is recommended to read the manual thoroughly before using the
product.

3. General Maintenance

To ensure optimal performance and longevity of the Multifunction
Power System, regular maintenance is required. Follow these general
maintenance guidelines:

• Refer to the General Maintenance Information section of this
  manual for detailed maintenance instructions.

• Perform routine inspections of the system for any signs of
  damage or wear.

• Clean the system regularly to remove any dirt or debris that
  may affect its performance.

• Check and replace filters, if necessary, following the
  recommended maintenance schedule.

• Keep all electrical connections clean and secure.

• Refer to the Owner’s Manual for any specific maintenance
  procedures or recommendations.

Frequently Asked Questions (FAQ)

Q1: What is the part number of the Multifunction Power

System?

A1: The part number of the Multifunction Power System is
D600014.

Q2: Where can I find detailed installation instructions?

A2: Detailed installation instructions can be found in the
Multifunction Power System (Cat) Installation Manual.

Q3: How can I contact VMAC Technical Support?

A3: You can contact VMAC Technical Support by calling
888-241-2289 or visiting the VMAC Knowledge Base at
kb.vmacair.com.

®
Installation and Owner’s Manual Multifunction Power System
(Cat C1.1 Engine ECU Equipped) D600014
www.vmacair.com

Table of Contents
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 General Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Multifunction Power System (Cat) Installation Manual . . . . . . . . . . 11
Installation Requirements and Considerations . . . . . . . . . . . . . . . . . . . . . . 13 Mounting Locations and Ventilation Requirements . . . . . . . . . . . . . . . . . . 14 Ventilation Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Mounting the Cat MF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Completing the Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Compressor Performance Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Multifunction Power System (Cat) Owner’s Manual . . . . . . . . . . . . . 25
Identifying Your System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 System Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Optional Equipment Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Control System Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Control System Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Starting and stopping the Cat MF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Cold or Hot Weather Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Battery Charging / Boosting and Welding . . . . . . . . . . . . . . . . . . . . . . . . . 44 Welding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Diagnostics Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Adjustable Parameters (User Setup) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
General Maintenance Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Maintenance and Repair Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Maintenance Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Regular Inspection Instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 General Service Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 500 Hour / 6 Month Service (Compressor) . . . . . . . . . . . . . . . . . . . . . . . . 63 1,000 Hour / 1 Year Service (Compressor) . . . . . . . . . . . . . . . . . . . . . . . . . . 67 500 Hour / 1 Year Service (Engine) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Diagnostics and Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 Electrical Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Air Receiver Tank. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Recommended Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 Accessory Products from VMAC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Warranty Registration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

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Document: 1930367 Changes and Revisions

Revision

Revision Details

E

ECN 23-017 Add VSI and update remote gen instr.

F

ECN: 23-224 Update VSI install instructions

Revised by
MSP MSP

Checked by Eng.
Tech. Qual. Mech. Elec. N/A CAB MSP LPH N/A CAB MSP N/A

Implemented
1 Aug. 2023 6 Dec. 2023

Additional Application Information
This manual applies to the Cat powered Multifunction Power System (Cat MF)
equipped with the Cat C1.1 engine (ECU Equipped). (P/N: D600014).

Registered Trademarks
All trademarks mentioned in this manual are the property of their respective owners. VMAC’s use of manufacturers’ trademarks in this manual is for identification of the products only and does not imply any affiliation to, or endorsement of said companies.

Loctite®, Loctite® 242 and Loctite® 567 are registered trademarks of Henkel AG & Company KGaA. Cat® and Caterpillar® are registered trademarks of Caterpillar Inc. and are used with permission. Espar is provided by Eberspächer Climate Control Systems GmbH & Co. KG. Shocker PASS® is a registered trademark of Headwind Automotive Solutions Ltd.
Important Information
The information in this manual is intended for certified VMAC installers who have been trained in installation and service procedures and/or for anyone with mechanical trade certification who has the tools and equipment to properly and safely perform the installation or service. Do not attempt installation or service without the appropriate mechanical training, knowledge and experience. Follow all safety precautions. Any fabrication for correct fit in modified vehicles must follow industry standard “best practices”.

Notice
Copyright © 2021 VMAC Global Technology Inc. All Rights Reserved. These materials are provided by VMAC for informational purposes only, without representation or warranty of any kind, and VMAC shall not be liable for errors or omissions with respect to the materials. The only warranties for VMAC products and services are those set forth in the express warranty statements accompanying such products and services, if any, and nothing herein shall be construed as constituting an additional warranty. Printing or copying of any page in this document in whole or in part is only permitted for personal use. All other use, copying or reproduction in both print and electronic form of any part of this document without the written consent of VMAC is prohibited. The information contained herein may be changed without prior notice.
Printed in Canada

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Safety
Important Safety Notice
The information contained in this manual is based on sound engineering principles, research, extensive field experience and technical information. Information is constantly changing with the addition of new models, assemblies, service techniques and running OEM changes. If a discrepancy is found in this manual, contact VMAC Technical Support prior to initiating or proceeding with installation, service or repair. Current information may clarify the issue. Anyone with knowledge of such discrepancies, who proceeds to perform service and repair, assumes all risks.
Only proven service procedures are recommended. Anyone who departs from the specific instructions provided in this manual must first ensure that their safety and that of others is not being compromised, and that there will be no adverse effects on the operational safety or performance of the equipment.
VMAC will not be held responsible for any liability, consequential damages, injuries, loss or damage to individuals or to equipment as a result of the failure of anyone to properly adhere to the procedures set out in this manual or standard safety practices.
Safety should be the first consideration when performing any service operations. If there are any questions concerning the procedures in this manual, or more information is required, please contact VMAC Technical Support prior to beginning work.
Safety Messages
This manual contains various warnings, cautions and notices that must be observed to reduce the risk of personal injury during installation, service or repair and the possibility that improper installation, service or repair may damage the equipment or render it unsafe.
This symbol is used to call attention to instructions concerning personal safety. Watch for this symbol; it points out important safety precautions, it means, “Attention, become alert! Your personal safety is involved”. Read the message that follows and be aware of the possibility of personal injury or death. As it is impossible to warn of every conceivable hazard, common sense and industry standard safety practices must be observed.
This symbol is used to call attention to instructions on a specific procedure that if not followed may damage or reduce the useful life of the compressor or other equipment.
This symbol is used to call attention to additional instructions or special emphasis on a specific procedure.

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Safety Precautions
As it is impossible to warn of every possible hazard that may result from operating this system, common sense and industry standard safety practices must be observed.
Read this information before operating the compressor. Follow the information and procedures in this manual for operation, maintenance and repair. Observe the following items to reduce the chance of personal injury or equipment damage:
Follow all safety precautions for mechanical work as rotating components, pressurized air, and hot surfaces may pose a hazard. Only qualified personnel should perform maintenance and repair on system components and only while the system is properly shut down and depressurized.
Proper service and repair are important to the safety of the service technician and the safe, reliable operation of the equipment. Always use genuine VMAC replacement parts.
The procedures described in this manual are the only authorized methods of installation, service and repair. Some procedures may require the use of tools specially designed for a specific purpose. Anyone using a replacement part, service procedure or tool must first determine that neither their safety nor the safe operation of the equipment will be compromised by the replacement part, service procedure or tool selected.
Personal Safety
· Do not breathe the compressor air as vaporized oil is a respiratory
hazard.
· Do not breathe engine exhaust, internal combustion engines
produce carbon monoxide, a poisonous odorless gas which can cause death. Do not start or operate this compressor in an enclosed area.
· Always use the appropriate personal protective equipment,
particularly eye and hearing protection when operating air powered equipment.
Burn Hazard
· The engine, exhaust and the compressor system get very hot
during operation, contact with the components or the oil can cause serious injury. Allow sufficient time for the system to cool prior to performing service.
· Avoid contact with the engine or compressor components until the
system has cooled sufficiently.

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Burst Hazard
This system is designed to generate air pressure up to 175 psi during normal operation (factory default: 150 psi):
· Serious injury or death may result from an air tank explosion. · Never exceed manufacturer’s maximum air pressure rating. · Do not repair components, only replace with approved parts. · Do not tamper with, or disable factory safety equipment.
Harmful Vapours
Breathing fuel vapours or engine exhaust can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.
· Always start and operate the engine in a well ventilated area. · Do not breathe engine exhaust. Internal combustion engines
produce carbon monoxide, a poisonous odorless gas which can cause death. Do not start or operate this system in an enclosed area.
· If in an enclosed area, vent the exhaust to the outside and ensure
there is adequate access to fresh breathable air.
Fire and Explosion Hazard
· Vaporized oil propelled by high pressure air is an explosive mixture. · Fire in the compressor can cause an explosion and flame projection.
Should this occur, there is potential for serious injury or death.
· Operate the compressor in a well ventilated area free of flammable
vapors, dust, or other combustible materials.
· Do not refuel the engine while the system is running or hot. · Do not refuel the engine in an enclosed space or area with poor
ventilation.
· If fuel is spilled, clean the area and wait for it to dry before
starting the engine.
· Never place objects against, or on top of, the compressor. · Never expose the system to extreme heat. · Do not use starting fluids (such as ether) as they can cause an
explosion.
· Accumulated oil and grease can cause the system to overheat and
pose a fire hazard. Keep the system clean and repair any leaks immediately.

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Compressor Air and Oil Hazard
· The compressor system is under sufficient pressure that a leak
could force the air/oil mixture through the skin directly into your bloodstream. This could cause serious injury or death.
· Ensure the system is completely depressurized before attempting
maintenance or repair.
· Do not use compressed air to clean off clothing or skin, compressed
air can penetrate the skin causing serious injury or death.
· Do not move or service the system while it is pressurized or
operating.
· Components and hoses under pressure could separate suddenly
and cause serious injury or death. If equipped, the air receiver tank must be drained prior to servicing the system.
· Never adjust or attempt to make any repairs to the system while
the engine is running. Components and hoses under pressure could fail and cause serious injury or death.
Moving Parts Hazard
· Before performing service, disconnect the negative battery cable
to prevent unexpected engine start.
· Do not operate the system without guards in place. If the guards
are damaged or missing, replace them before operating the equipment.
Electrical Hazard (Electrical connections)
· Ensure the ground point connection from the Cat MF is connected
to the vehicle body/chassis to prevent the chance of damage to the equipment or personal injury.
· Ensure the vehicle is grounded appropriately.
Electrical Hazard (Generator)
The generator produces potentially lethal voltages and current:
· Do not tamper with, or modify, the generator. · Do not bypass any safety features built into the Cat MF. · Do not service the generator unless qualified to do so. · Do not operate the MF unless this manual has been read in its
entirety.

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Lead Acid Battery Hazard
Working near lead acid batteries is dangerous. Batteries may generate sulphuric acid and explosive gases during regular operation. Lead acid batteries may explode if exposed to a spark.
· Follow all safety precautions when jump starting or charging a
battery.
· Never attempt to jump start a frozen battery. · Never overcharge a battery.
General Warnings
· Disconnect the negative battery cable prior to attempting any
repair or service.
· Be cognizant of unexplained changes in operation and record any
changes.
· Check the engine and compressor oil levels and condition prior to
starting the system.
· Do not add or change oil while the system is running. · Use only approved oils. · Inspect the equipment before every use. · The compressor may operate anytime the engine is running. Avoid
contact with the compressor, hoses, or engine during operation.
· While in “Standby”, the Cat MF may start at any time. · Keep hoses and wiring away from hot, sharp, or moving
components.
· Use only approved hoses and replacement parts. · Do not modify the equipment. · Do not operate the Cat MF unless this manual has been read in its
entirety.
· Do not operate the Cat MF when fatigued or under the influence of
alcohol or drugs.
· Never bypass or disable any of the safety equipment. · Never adjust, or attempt to make any repairs, to the Cat MF while
the engine is running unless expressly instructed to do so.
· Components and hoses under pressure could fail and cause serious
injury or death.
· Loose fasteners or components can damage equipment, ensure all
fasteners and components are properly torqued or secured.

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Warranty

VMAC Standard Warranty (Limited)
For complete warranty information, including both VMAC Standard Warranty (Limited) and VMAC Lifetime Warranty (Limited) requirements, please refer to our current published warranty located at: www.vmacair.com/warranty

If you do not have access to a computer, please contact us and we will be happy to send you our warranty.

VMAC’s warranty is subject to change without notice.

VMAC Lifetime Warranty (Limited)

A VMAC Lifetime Limited Warranty is offered

AIR INNOVATED

on the base air compressor only and only on

UNDERHOOD, Hydraulic Driven, Transmission Mounted, Gas and Diesel Engine Driven Air

LIFETIME

Compressors, Multifunction Power Systems, and other products as defined by VMAC, provided that (i) the purchaser fully completes and submits a

WARRANTY
TRUST SERVICE VALUE

warranty registration form within 3 months of purchase, or 200 hours of operation,

whichever occurs first; (ii) services are completed in accordance with the Owner’s

Manual; (iii) proof of purchase of applicable service kits are made available to

VMAC upon request.

The VMAC Lifetime Warranty is applicable to new products shipped on or after 1 October, 2015.

Warranty Registration

The VMAC warranty registration form is located near the back of this manual. This warranty registration form must be completed and sent to VMAC at the time of installation for any subsequent warranty claim to be considered valid.

There are 4 ways the warranty can be registered with VMAC:

www.vmacair.com/warranty

warranty@vmacair.com
877-740-3202 VMAC – Vehicle Mounted Air Compressors 1333 Kipp Road, Nanaimo, BC, Canada V9X 1R3

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VMAC Warranty Claim Process
VMAC warranty work must be pre-authorized by VMAC. Claims are processed via our dealer network. If you are not a VMAC dealer, please select one to work with via our Dealer Locator: https://www.vmacair.com/dealer-locator/

1. Communicate with VMAC Technical Support at 1-888-241-2289 or tech@vmacair.com to help diagnose/troubleshoot the problem prior to repair. VMAC technical support will require the VMAC System ID, and hours on the compressor.
2. VMAC will provide direction for repair or replacement of the failed components.
3. If requested, failed parts must be returned to VMAC for evaluation. 4) Dealers may login to the VMAC website to view the “VMAC Labour Time
   Guide” (under “Agreements”) to see the allowable warranty labour times. 5) Warranty invoices must include the Service Ticket number, VMAC System ID#,
   hours on the compressor, and a detailed description of the work performed. 6) VMAC Warranty does not cover consequential damages, overtime charges,
   mileage, travel time, towing/recovery, cleaning or shop supplies. 7) Dealers submit warranty claims on behalf of the Vehicle Owner/End User
   affected by the defective part(s). The dealer ensures that all warranty credits are refunded back to the Vehicle Owner/End User who made the initial warranty claim.
   In order to qualify for Lifetime Warranty (Limited), the completed warranty registration form must be received by VMAC within 3 months of the buyer receiving the Product(s), or 200 hours of operation, whichever occurs first. If the completed warranty registration form has not been received by VMAC within 3 months of the buyer receiving the Product(s), or 200 hours of operation, the “Standard” warranty period will be deemed to commence 30 days from the date of shipment from VMAC. Failure to follow the warranty claim process may result in denial of the warranty claim.
   VMAC Product Warranty Policies & Warranty Registration can be found on the VMAC website (see previous page for URL).

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General Information
Introduction
This manual provides installation guidelines, operating instructions, specifications, adjustment, maintenance and warranty information for the Cat MF. Read this manual, as well as the Cat C1.1 Operation and Maintenance Manual (P/N:1930372) prior to installation, operating or servicing the Cat MF.
Follow all safety precautions when operating or servicing the Cat MF.
Proper service and repair are important to the safety of the operator and the safe, reliable operation of the equipment. Always use genuine VMAC parts.
The procedures described in this manual are the only approved methods of service and operation.
Hose Information
The hoses used in VMAC compressor systems have a specific inner liner that is compatible with VMAC compressor oil. Use of hoses other than those supplied or recommended by VMAC may cause compressor damage and may void your warranty. Please contact VMAC for replacement hoses and further information.
Ordering Parts
To order parts, contact a VMAC dealer. The dealer will ask for the VMAC System ID (see page 27), part number, description and quantity. Locate the nearest dealer online at www.vmacair.com/dealer-locator or call 1-877-912-6605.

Additional Support
Additional resources such as installation manuals, illustrated parts lists, the VMAC Knowledge Base, air tool consumption guides, etc. are available at https://www.vmacair.com/support/.

Preparation for installation and / or operating the MF is very important. Missing a step can cause problems in the installation or with the operation of the system and may damage to components.
Check off each item as it is completed so that steps are not
missed.

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®
Multifunction Power System (Cat) Installation Manual

Installation Requirements and Considerations

The information in this section is critical to ensure proper operation of the system. Read these requirements prior beginning the installation.
Failure to adhere to these requirements may cause the Cat MF to operate erratically or impact the overall quality of the installation.

In order for the system to enter “Standby” mode and automatically shut down, an air receiver tank rated for 200 psi, with a minimum capacity of 5 USG, is required.
Requirements:
· Ensure there is adequate clearance around the unit to provide good air
circulation and effective cooling (see page 14).
· Ensure the service panel is accessible. · Ensure the engine and compressor oil level can be checked easily. · Ensure the unit can be serviced easily (i.e. without having to disconnect hoses,
or reposition/remove the unit).
· Ensure the hose lengths are as short, and with the least amount of 90°
fittings, as possible.
· Ensure the unit is mounted in a location where hot air and/or exhaust will not
recirculate into the system.
· Ensure the exhaust is routed to open air without being orientated in a way
that will accumulate of water.
· Ensure the unit is protected from excessive exposure to the elements. · Ensure the unit is protected from damage from other operations. · Ensure the intended mounting location is capable of safely supporting a
minimum of 710 lb (322 kg).
· Ensure the unit is sufficiently isolated from vibration to prevent damage to the
frame and other components.
Considerations:
· Is the intended location convenient for electrical and air connections? · Will the unit be mounted away from heat sources such as engines, exhaust, or
other components that can generate heat?
· Will the unit be mounted where it will be exposed to high contamination levels,
including combustible gases?
· Will the unit be fueled via the optional 7 gallon fuel tank (P/N: A500204) or
via the vehicle’s fuel tank (diesel fuel only)?
· Will the unit be used in temperatures below -5 °C (23 °F)? If so, VMAC
recommends ordering the system with the optional Cold Climate Kit.

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Mounting Locations and Ventilation Requirements

Top mounted (Preferred)

Enclosure mounted (Not recommended unless mounted on a pull out drawer)

Not recommended
VveMhAicCledaosetshneodtFrriagegucorcemre1ma–teenddMwmohuoenuntnintthginelgovcteahhteiicoulnensiitsamt otvhiengbaccakusoefsthdeebris to be deposited (and accumulated) inside the unit.

Top Mounting (Preferred mounting location)
Placing the Cat MF on top of the service body provides the best access to cool fresh air. Maintain a minimum of 12 in between the sides of the Cat MF and all other solid objects. Ensure there is an ample supply of cool air to the service panel side of the Cat MF and that the hot air exhausted from the radiator can escape the area unrestricted (Figure 1).
Enclosed Mounting
Enclosed mounting is not recommended due to the risk of recirculating exhaust and the significant heat generated by the Cat MF.
Mounting the Cat MF in an enclosure will limit access to cool fresh air, restrict the escape of hot air from around the unit and have an adverse effect on cooling the system; ensure adequate ventilation is provided. If mounting in an enclosure, VMAC strongly recommends mounting the unit on a pullout drawer with a switch that prevents the unit from being operated unless the drawer is fully extended.
While it is not possible to make absolute recommendations regarding ventilation (due to the widely differing circumstances that are possible), duty cycle, ambient temperature and enclosure shape are some of the important variables that must be considered.

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Ventilation Requirements
Ventilation Requirements
Adequate ventilation is vital for safety. Ensure the engine exhaust is directed away from any passenger compartments or enclosed areas where personal may be working.
Systems without adequate cool air flow may experience stalling, premature oil deterioration, increased oil consumption, power loss, and reduced life or failure of the engine and/or compressor.
If the compressor overheats, the intelligent control features will shut the engine down and prevent restart until the oil temperature drops below 140 °C (284 °F).
Exhaust and waste heat from the Cat MF must be vented away from the system to prevent the diesel engine from ingesting its exhaust and stalling.
Cool air is drawn into the unit via the service panel while the hot air is pushed away from the unit via the engine radiator fan.
During operation, the Cat MF generates a considerable amount of heat that must be evacuated from the unit to allow it to run efficiently. While the engine is liquid cooled, it requires an adequate supply of cool fresh air to cool the engine and allow proper fuel combustion.
Ensure there is a minimum of 12 in of clearance between the service panel and radiator grille and any other components mounted on the vehicle.
The engine exhaust must be vented away from the Cat MF and toward a safe location. If mounted in an enclosure, or the bed of a pickup truck box, the exhaust must be vented outside of the vehicle to prevent the engine from ingesting its exhaust and overheating or stalling.

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Mounting the Cat MF
External dimensions
Locate a suitable mounting position for the Cat MF. Place the unit in its
intended location and check clearances to any other objects (Figure 2). All dimensions are in inches. 34 5/16
31 5/16
29 3/4 24 13/16

6 1/4

19 3/4 Figure 2 — External dimensions

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CAT MF Base Plate
The base plate has 12 pre drilled holes that can be used to mount the system. New holes can be drilled in any location provided they do not interfere with the vibration isolator mounts. All dimensions are in inches.
17
28
18 32

Ø7/16 Figure 3 — Base plate

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Installing the Cat MF
While the Cat MF is manufactured with heavy duty vibration isolators between the engine and the base plate, VMAC recommends installing additional vibration isolators if the vehicle will be driven off of paved roads to prevent impact damage to the frame and other components.
Secure the Cat MF to the vehicle using a minimum of (×4) 3/8 in or 10 mm bolts
(×2 on each end) with washers, and either lock washers or Loctite 242 (blue). Fuel Supply
All dimensions are in inches. If the Cat MF will be fueled via the vehicle’s diesel fuel tank, do not plumb the fuel line into the lower section of the fuel tank.
Connect the Cat MF to the vehicle’s diesel fuel tank, via the VMAC Fuel pump
Kit (P/N: A500030), or the optional 7 gallon external fuel tank (P/N: A500204). Air Discharge
Remove the #12 cap from the air outlet (located on the exhaust side of the unit)
and connect the Cat MF to the receiver tank (sold separately, see “Accessory Products from VMAC” on page 103). Exhaust
Ensure the exhaust pipe has suitable clearance from, and will not contact, any flammable materials.
If extending the exhaust, a suitable flex coupling or flex pipe must be used to prevent damage to the muffler and exhaust system. Dependent upon the length of the extension, extra support may be necessary.
If the exhaust will be oriented up, such as with the 90° exhaust elbow (P/N: A500198), ensure an appropriate flapper is installed to prevent water accumulation in the exhaust system.
The upfitter must supply an exhaust pipe suitable to the application. The muffler has a 1 5/8 in ID outlet.
Install an adequate exhaust pipe (not supplied) suitable to the application.

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Electrical Connections
Failure to sufficiently ground the Cat MF could cause severe injury or death due to electrical shock and static discharge. While the American Welding Society® Safety & Health Fact Sheet No. 29 (Grounding of Portable and Vehicle Mounted Welding Generators) is a great reference for grounding the Cat MF, VMAC recommends working/consulting with a certified electrician and local regulatory bodies when grounding the Cat MF. Certified electricians and local regulatory bodies can assist with any questions or concerns regarding proper grounding, and compliance with local regulations.
The Cat MF must be grounded to the vehicle frame (or an earth ground when not mounted to a vehicle) to prevent electrical hazards. The vehicle mounted ground connection must be made by bare metal to metal contact to the vehicle frame as some service body materials (e.g. plastics, wood, bedliners, etc.) may insulate the Cat MF from the frame, resulting in inadequate grounding.
If permanently connecting the Cat MF to the vehicle battery, a battery isolator or circuit must be installed.
Main System Ground (Vehicle Mounted)
Connect a ground wire with a minimum size of 10 AWG to the ground terminal
located on the engine side of the unit, next to the air outlet (Figure 4).

Figure 4 — Connect ground wire
Connect the other end of the ground wire to the vehicle frame via a minimum
3/8 in post (this connection must be bare metal to metal contact).

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Main System Ground (Non-Vehicle Mounted Applications)
Connect a ground wire with a minimum size of 10 AWG to the ground terminal
located on the engine side of the unit, next to the air outlet (Figure 4).
Connect the other end of the ground wire to an earth ground device that
complies with local electrical codes concerned with earth grounding devices.
Display Panel
The Display Box, rocker switches, and Welder Control Box are splash resistant, not weather proof; ensure they are mounted where they will be protected from rain, snow, mud, direct sunlight, etc. (e.g. inside the cab, service body, or a cabinet).

VMAC recommends that the harness extensions be soldered and sealed with heat shrink tubing, or sealed butt splices (not supplied) to provide durable, and moisture resistant connections.

The Cat MF is shipped with male and female connectors (with pig tails) to facilitate making extension harnesses to connect the various components.
Mount the Display Panel in a convenient location that is protected from the
weather.
Using the included connectors with pig tails, connect the (×4) Display Panel
connectors (Table 1).
Recommended Wire Gauge for Display Panel Harnesses Extensions

Wire Description

Wire Gauge Up to 10 ft 10 ft to 16 ft 16 ft to 22 ft

Display box connections (4 pin connector)

18 AWG

18 AWG

18 AWG

Rocker switches (compressor, generator, etc.)

18 AWG

18 AWG

18 AWG

Key switch (yellow)

18 AWG

18 AWG

18 AWG

Key switch Return power (orange) 14 AWG

12 AWG

10 AWG

Supply power (red)

14 AWG

12 AWG

10 AWG

Table 1 — Display Panel harness connections
Welder Control Box
The Welder Control Box includes an 8 ft harness with (×4) plugs.
Plug one side of the “T” harness with the (×2) flat 5-pin connectors into the
matching connector at the MF unit and the other side into the connector running to the rocker switches on the Display Panel. Note: If using the pigtail extension harness, the welder control box should be installed on the side closest to the rocker switch panel.
Connect the (×2) Welder Control Box connectors into the matching connectors
in the main harness bundle.

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Optional Equipment
Remote Start Wire The Cat MF can be started remotely using a remote start wire running to the Control Box. A blunt cut yellow wire can be found near the Control Box (located inside the service panel). With the key-switch in the “RUN” position, the remote wire can be grounded to start the system. Once the ground is interrupted, the control system will stop the engine.
Connect the yellow remote start wire to one of the terminals on a Single Pole,
Single Throw (SPST) switch and connect the other terminal to ground on the Cat MF. Installing Power Take Off (PTO) driven equipment (VMAC supplied PTO only)
If installing aftermarket PTO pump / equipment, see page 36 for PTO port parameters.
Ensure any equipment mounted to the PTO is rated for 2,800 rpm and the output does not exceed 20 hp.
Remove the PTO cover plate located near the air discharge. Ensure the output shaft of the PTO rotates freely prior to mounting any
equipment. Espar Heater Connections (×2) 1/2 in ports are provided for integration with an Espar heating system. The ports are located below the air discharge on the exhaust side of the system.
· Lower Port: Inlet from Espar. · Upper Port: Return port to Espar.

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Completing the Installation

Ensure all hoses, tubes or wires related to the installation are secured so that they will not contact any hot, sharp or moving parts and that adequate steps are taken to mitigate any wear due to equipment vibration.

Ensure the following steps have been completed prior to operating the Cat MF for the first time.

Verify the following fluids are at the correct level:
Check the engine coolant level. Check the engine oil level. Check the fuel level. Check the compressor oil level.
Perform a final inspection to ensure that:
Ground point is connected. Fasteners and connections are tight. Hoses are secure and adequately protected. Wiring is secure and adequately protected. All air outlets / ball valves are closed.
Testing the System
Connect a VMAC Air Test Tool (P/N: A700052) to the output of the air receiver
tank (not the Cat MF discharge outlet; connecting the test tool directly to the Cat MF is only required when performance testing the compressor itself).
Install the 60 cfm orifice into the air test tool. Turn the fuel supply valve to the “ON” position.
Prime the Fuel System:
Turn the key switch to the “ON” position for 2 minutes. Turn the key switch to the “OFF” position. Turn the key switch to the “ON” position. Press the “ENTER” button to start the engine and allow it to reach normal
operating temperature.
Check the system for any leaks. Engage the generator by pressing the rocker switch (located on the Display
Panel) to “ON”.
Allow the system to run with the generator engaged for a minimum of 1/2 hour. This test ensures that the system has adequate ventilation.
Turn off the generator by pressing the rocker switch (located on the Display
Panel) to “OFF”.
Press the “ENTER” button to shut down the system. Turn the Key switch to “OFF”.

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Compressor Performance Testing
Compressor Performance Testing
System operation can be tested using the tools that will be operated by the system or by using the VMAC Test Tool (A700052) with the appropriate orifice in the outlet to simulate tool use (Figure 5).

JIC Adapters

Orifice

Ball valve

Install orifice here
Figure 5 — A700052 VMAC Air Test Tool
Disconnect all downstream equipment (hose reels, etc.) and connect the test tool directly to the discharge fitting on the Cat MF.
Ensure there are no leaks in the test tool. The system may not idle down or enter standby if there are leaks in the lines or fittings.
Install the VMAC test tool at the Cat MF outlet with the 60 cfm orifice. Ensure the ball valve is closed. Start the system and allow it to reach normal operating temperature. After the system has reached normal operating temperature, observe the
pressure gauge on the test tool. The pressure should be approximately 150 psi.
Open the ball valve on the test tool and observe the pressure gauge.
If the system is not able to maintain air pressure at 95 psi when the ball valve is opened fully, the compressor has failed the performance test.
Close the ball valve slowly to allow the system pressure to rise. The Cat MF can be shut down normally unless the control system is being
tested.
Control System Testing
When the pressure reaches 150 psi (factory default setting), the system will
“unload” and air should be heard to escape from the inlet.
After 5 minutes without air use (factory setting), and with the PTO and generator
turned off, the system will go into standby and the engine will shut down.
While in standby, the system will continue to monitor the battery voltage, system temperature, air use, and air pressure and will restart as needed to maintain operating parameters.

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®
Multifunction Power System (Cat) Owner’s Manual

Identifying Your System
The System ID will be requested any time that parts are ordered, when calling for technical support, or submitting a warranty claim.
The system ID is the preferred method of identifying the system as it serves as a master record of all of the components in the system. The system ID plate is found on the Air Oil Separator Tank (AOST) mount of the Cat MF (Figure 6).

Figure 6 — System ID location
An alternative method of identifying the system is via the compressor serial number which is found on a plate attached to the compressor. This is a less desirable method of identifying the system as it may not link back to the original system if the compressor has been replaced.
System ID breakdown
The system ID provides specific information about the system such as the model, revision, production date and the unique identifier (Figure 7).
D600014 A BC 123

Model number

Unique identifier

Revision letter

Production date code

Figure 7 — System ID breakdown

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System Components

Components

The Cat MF consists of the following components (dependent upon model and/or

optional features):

· Air Oil Separator Tank (AOST).

· Power Take Off (PTO) / Hydraulic Pump.

· Compressor.

· Generator.

· Oil cooler.

· Digital display panel.

· Coalescing manifold.

· Remote Genset / Welder Control Box.

· Control box / engine diagnostic lamp. · Positive Air Shutoff System (PASS).

AOST

Air/oil discharge from
compressor

Oil sight glass

Oil filter
Oil supply to compressor
Figure 8 — AOST (service panel side)
Generator (for reference only)

Oil drain

12 hose to coalescing filter

Figure 9 — AOST (radiator side)

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Compressor Clutch

Inlet valve

Air filter

Air/oil discharge

Oil supply
Figure 10 — Compressor assembly Compressor Oil Cooler

Temperature sensor

Cooled oil (to compressor)

Engine coolant (to lower radiator hose)

Hot compressor oil (from AOST)

Engine coolant (to engine water pump)
Figure 11 — Compressor oil cooler

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Coalescing Manifold Pressure sensor

200 psi pressure relief valve

Oil scavenge

Air discharge (to customer equipment)
Air discharge (from AOST)
Figure 12 — Coalescing manifold Control Box / engine diagnostic lamp

Air solenoid
Coalescing filter

Control box
Engine diagnostic lamp

Figure 13 — Control box

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PTO and Hydraulic Pump

Hydraulic pump

Air discharge (for reference only)

Generator

PTO Figure 14 — PTO pump (optional equipment)

Generator

Figure 15 — Generator

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Positive Air Shutoff System PASS

Air intake

Figure 16 — Positive Air Shutoff System Remote Genset / Welder Control Box

ARC FORCE knob

Weld/Charge selection knob

Current knob

Weld alarm light

Error LED

Voltmeter

Weld interlock button

Reset button

On/Off LED

Figure 17 — Remote generator control box with Voltage Sense Interlock

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Digital Display Panel The digital display panel serves as the operator’s control panel and contains the ignition key switch, the display LED (displays information such as compressor hours, service reminders, warning messages, error codes, adjustable paramaters, and diagnostic information), the display box navigations buttons, the rocker switches used to operate the optional components (such as PTO and generator), and the “READY” and “WARNING” lights.

Display LED

Enter button Ignition key switch

Accessory rocker switches

Navigation buttons

Status lights

Figure 18 — Digital display panel

Hoses / Tubes
VMAC compressor systems include hoses that include an AQP inner liner that is compatible with VMAC compressor oil. The PTFE tubes used in VMAC systems are rated for the high temperatures VMAC compressors generate. Use of hoses or tubes other than those supplied or recommended by VMAC may fail and/or cause compressor damage and may void warranty. Please contact VMAC for replacement hoses or tubes or for further information.
· Hoses must have an AQP liner. · Oil scavenge and pressure control tubes must be appropriately rated PTFE.

VMAC Compressor oil will degrade rubber lined hoses, use only hoses with an AQP elastomer type liner. Contact VMAC Technical Support at 1-888-241-2289 for further information.

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System Specifications
The Cat MF is powered by the Cat C1.1; this 24 hp (18.4 kw) naturally aspirated, 3 cylinder diesel engine drives a 45 cfm VMAC air compressor. Average fuel consumption is approximately 1.5 g/h (5.6 l/h). Engine speed
· Base idle: 2,300 rpm – 2,325 rpm. · High idle (generator on, no load): 2,800 rpm – 2,850 rpm.
Air Compression
The Cat MF uses a VMAC designed and manufactured flooded lobe, rotary screw compressor. The oil filled compressor housing contains (×2) rotors. Compression occurs when air (at normal atmospheric pressure) enters a chamber where it is trapped between meshing rotor lobes. Cooled oil is injected into the rotors during compression to lubricate the rotors and bearings, absorb the heat of compression, and seal the rotor lobes to allow for efficient compression. As the rotors rotate, the meshing lobes compress the volume of the trapped air/oil mixture before sending it, via the discharge line, to be cooled and separated by the AOST.
When the compressor switch is in the “ON” position, air pressure is monitored via a pressure sensor mounted in the coalescing manifold. The intelligent control system monitors the air pressure and will respond if the pressure drops below the configurable top up pressure and / or high air rate (see “Adjustable Parameters (User Setup)” on page 49).
The compressor clutch is electronically controlled and will automatically disengage when the engine speed drops below 2,550 rpm, to ensure the generator frequency remains within acceptable parameters.
PTO loads are not directly monitored or controlled.
Air Pressure Regulation
Air pressure regulation is achieved via an inlet valve and is adjustable via the Display Box. The system pressure (factory set at 150 psi) can be adjusted between 80 psi and 175 psi. VMAC recommends the use of a Filter Regulator Lubricator (FRL) to reduce the operating pressure delivered to the tools.
Adjusting the pressure higher than the default will increase the load on the compressor and will reduce the power available to run other loads such as the PTO.
Compressor Oil Separation and Cooling
The system utilizes a 2 stage air/oil separator. The hot air/oil mixture from the compressor enters the AOST and is mechanically separated with internal baffles. The second stage uses a spin-on coalescing filter to remove the remainder of the oil from the air stream.

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The small amount of oil recovered from the coalescing filter is returned directly to the compressor via a 1/4 in PTFE scavenge tube.
The hot compressor oil is directed to VMAC’s liquid to liquid cooler (which is integrated into the diesel engine’s coolant system) before being returned to the compressor.
Filtration
VMAC rotary screw compressors are designed and machined to exacting standards. Foreign particles entering the compressor can damage components such as rotors, bearings, seals, and the housing resulting in performance and efficiency losses, and reduced system life.
The system is equipped with a replaceable paper element air filter, a high pressure spin-on oil filter, and a spin-on coalescing filter.
Safety Features
A 200 psi (1380 kPa) pressure relief valve is installed in the coalescing filter manifold to prevent over pressurization. The Cat MF is also equipped with an integrated rapid blow down system that, via an air solenoid connected to the air bleed muffler (mounted on the compressor inlet), automatically discharges pressure upon shutdown.
Temperature sensors are installed in the compressor and the engine. In the event that the air/oil, or engine coolant temperature increases above a safe level, the system will shut down the engine, illuminate the “WARNING” light on the Display Box and log the error message.
Do not disable or bypass any safety components. Disabling or bypassing safety components could result in equipment damage, injury or death.

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Optional Equipment Specifications
Most of the optional equipment (listed below) is requested at the time of ordering and installed at the factory, however, some of these options are available as accessories and can be retrofitted to the unit.
Power Take Off (PTO)
The Cat MF is available with an optional SAE­A PTO port (located beside the air discharge port on the exhaust side of the system).
The PTO port is capable of delivering up to 20 hp via a serpentine belt and a 12 V clutch.
In addition to the PTO port option, VMAC offers the following hydraulic pumps:
· 10 GPM @ 3,500 psi (continuous), 4,200 psi (max). · 8 GPM @ 3,500 psi (continuous), 4,200 psi (max). · 5 GPM @ 3,500 psi (continuous), 4,200 psi (max).
Ensure any equipment mounted to the PTO is rated for 2,800 rpm and the output does not exceed 20 hp.
Shaft driven, and high inertia loads may require special considerations, please contact VMAC Technical Support for more information.
Generator
The Cat MF is equipped with:
Ac/dc generator / welder / battery charger / light duty battery booster
· ac: 8 kW continuous output with 1 × 30 A, 240 V, 60 Hz 3 phase circuit, 2 × 20
A, 120 V, 60 Hz single phase circuit with terminal strip.
· dc: “Constant Voltage” modes, 12 V ­ 48 V (selectable) for battery boosting
and charging; “Constant Current” modes for welding. Light duty battery booster / charger: 12 V dc and 24 V dc modes for battery
boosting (up to 300 A). Welder: This setting produces “Constant Current” output for arc welding.
Positive Air Shutoff System (PASS)
The Shocker PASS is capable of sensing possible engine “run away” situations, and will automatically close a valve in the engine air intake, causing the engine to shut down.
This is (generally) considered required safety equipment when diesel engines are used where flammable gases may be present (such as a mines).

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VMAC Cold Climate Kit
VMAC’s cold climate kit consists of a 110 V ac heater cartridge installed in the compressor housing, a 110 V ac pad heater installed on the engine oil pan, and a 110 V a/c heater installed in the engine block to warm the coolant.
The VMAC Cold Climate Kit requires connection to either a 1,500 W power inverter (minimum) or ac “shore power” in order to power the heater cartridges.
Dependant upon ambient temperature, the heaters may need to be energized for up to 90 minutes prior to attempting to start the system.
Espar Heater Connections
When integrated with the vehicle’s Espar heater, the system will automatically circulate warm coolant through the engine to aid in cold weather starting and operation. This is accomplished without any interaction with the VMAC control system.

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Control System Features
The Cat MF features an intelligent control system that monitors and manages various components, some of which are listed below:
· Multiple adjustable system parameters including: restart options, delayed
restart, system pressure, etc.
· Hour meter. · Starting and stopping the Cat MF (via the key switch on the Display Box,
remote wire, or the optional crane remote interface (P/N: A500029).
· Automatic engine shutdown if no air use is detected.
If equipped with the optional external fuel tank, the control system will monitor the fuel level and shut the system down to prevent the system from running dry.
· Automatic engine restart. The system will restart from Standby when the
system detects: high air use, air pressure drops below the reconfigured threshold, the system detects that the engine or compressor temperature drops too low, or the battery voltage gets too low.
If connected the vehicle’s engine battery, the Cat MF will monitor the vehicle’s battery and automatically restart to charge it as required.
· Air filter restriction warning. · Engine load detection will prioritize the generator and PTO, disabling the
compressor if needed to maintain engine rpm.
· Monitor system air pressure and disengage the compressor clutch in the event
of overpressurization.
· Engine monitoring and error logging:
Engine under speed.
Engine over speed.
Running when not expected.
No tachometer signal.
Starting error.
Low oil pressure.
· Separate error and warning message logging for both the engine and VMAC
systems.
· 500 hour and 1,000 hour compressor service reminders. · 500 hour engine service reminders. · LED lights warn that the system is in standby and may restart unexpectedly. · Audible buzzer and LED lights warn when the system is about to start.

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Control System Terminology
The following messages will appear on the Display Box to indicate the system state at a given time (key switch in the “ON” position). “SYSTEM READY” The Cat MF has completed its self diagnostic test and is ready to be started by:
· Pressing the “ENTER” button. · Turning the key switch to the “START” position for 1 second and then releasing
the key.
· Grounding the remote start wire.
“GLOW PLUG” The glow plugs are energized. The glow plugs will be energized for between 1 and 15 seconds dependent upon the engine temperature.
Once the glow plugs are energized, the engine restart alarm will sound for 3 seconds and pause for 3 seconds until the engine starts.
“STARTING” The control system will attempt to start the engine. The starter will be engaged for up to 15 seconds. If the engine fails to start after 3 attempts, the system will log error code 35, “ENGINE CRANK TIME OUT”. “WARMING” The control system is monitoring the engine temperature. The system will remain in the “WARMING” state until the engine reaches 5 °C (41 °F). “RUNNING” Once the engine coolant temperature reaches 5 °C (41 °F), the system will enter the “RUNNING” state. The system is ready for the compressor, PTO, or generator to be engaged. If no demand is placed on the system (generator and PTO are turned off, compressor is turned off, or has built to full system pressure), the “delay to unload” timer will begin counting down. “STARTING CLUTCH” The compressor clutch is engaged to allow the system to build air.
The control system will prevent the compressor clutch from restarting until pressure inside the compressor has had a chance to dissipate. If the compressor switch is engaged while there is still pressure in the system, the “STARTING CLUTCH” message will be displayed.

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“UNLOAD”
Once the “TIME TO UNLOAD” timer reaches 0M:00S, the control system will disengage the compressor clutch and reduce the engine speed to base idle (provided that neither the generator or the PTO are engaged).
While in the “UNLOAD” state, the control system will continue to monitor the air use rate and restart pressure. If the control system detects air use, it will return the system to the “RUNNING” state, engage the compressor clutch, and increase the engine rpm to the second speed, to meet the demand.
If no demand is placed on the system (generator and PTO are turned off, compressor is turned off, or has built to full system pressure), the control system will start the “TIME TO STANDBY” timer.
Any time that the PTO and/or generator are engaged, the “TIME TO STANDBY” timer will pause at 10 seconds and the system will be prevented from entering “STANDBY” until the PTO and/or generator are turned off.
“STANDBY”
Once the “TIME TO STANDBY” timer reaches 0M:00S, the control system will shut down the engine. While in “STANDBY”, the control system will continue to monitor air pressure, air rate, battery voltage, and engine temperature. The control system will automatically restart the engine if the PTO or generator is activated, or in response to the adjustable parameters (see “Adjustable Parameters (User Setup)” on page 49).
While in “STANDBY”, the strobe lights will flash to indicate that the engine may start unexpectedly.
If the control system sends a signal to start the engine, an audible alarm will sound to indicate that the engine is starting.
By default, the “DISABLE AUTO RESTART DELAY” is set to 60 minutes. After 60 minutes in “STANDBY”, the system will shut down completely (including the strobe lights) even though the ignition key remains in the “ON” position. To start the system again, turn the ignition key to “OFF”, then back to “ON”, and follow the normal startup procedure.
See “Adjustable Parameters (User Setup)” on page 49 for more information on restart delay.
“STOPPING”
When the system is running and the “ENTER” button is pressed, the system will enter the “STOPPING” state.
Once in the “STOPPING” state, the stop solenoid will engage for 10 seconds to allow the system to shut down. If the system is still pressurized, it will blow down air pressure from the compressor and the AOST.

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Starting and stopping the Cat MF
Prior to Operating the Cat MF:
Ensure the system is not mounted (or parked) on grades exceeding 15° as this
will affect lubrication and air/oil separation (Figure 19).

Figure 19 — Do not exceed 15° grade
If installed inside a cabinet or enclosure, open the door or cover completely and secure in the open position to provide proper ventilation
Startup Procedure
If the temperature is below -5 °C (23 °F), enable the Cold Climate kit heaters.
The time required for the heaters to sufficiently warm the Cat MF prior to attempting to start it, will depend upon the ambient temperature.
Check the compressor oil level at the sight glass in the AOST. Check the engine oil level. Check the engine coolant level. Check for any fluid leaks around the unit. Ensure any air tools, or installed ancillary equipment (e.g. PTO driven
equipment), is securely connected and the air discharge valve is closed.

If the Cat MF has not been started for several weeks, prime the fuel system prior to attempting to start the unit (page 22).

Turn the key switch to the “ON” position.
The Display Box will go through a self diagnostic check; if no errors are detected, the system will move into the “ready” state.
Press the “ENTER” button (or turn the key switch to “START”, hold it there for
approximately 1 second, then release it.
The Display Box will indicate “GLOW PLUGS ENABLED”. The glow plugs will be active for between 1 and 15 seconds, dependent upon the ambient temperature.
Once the glow plugs are energized, the engine restart alarm will sound for 3 seconds and pause for 3 seconds, until the engine starts.

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After the glow plugs have sufficiently warmed the intake, the Display Box will indicate “SYSTEM IN START MODE”, after which the engine will crank.
If the engine coolant temperature is below 5 °C (41 °F), the Display Box will display “ENGINE WARMING” and the control system will prevent the engine speed from increasing or engaging the compressor clutch, PTO or generator. Once the control system detects that the engine coolant has reached 5 °C (41 °F), the PTO, generator, and compressor can be engaged. If no demand is made on the system (e.g. the compressor has built to full system pressure, or the PTO, generator or compressor are not engaged), the system will enter the “UNLOAD” state and a countdown will start before the system enters “STANDBY” and shuts down.
Additional Information
While the system is running, additional information such as air pressure, air rate, engine speed, engine temperature, battery voltage, time to unload / standby, compressor temperature, can be viewed by pressing the “” and “” buttons. To return to the “SYSTEM RUNNING” menu, press the “” button.
Shutdown Procedure
Prior to shutting down the Cat MF, allow the system to build to full system pressure, then turn off the compressor, PTO and generator and allow the engine to reduce to base idle.
Turn off the compressor via the rocker switch. Turn off any PTO driven equipment. Turn off any electrical equipment. If the electrical equipment cannot be
completely powered down (e.g. an LED indicator light remains on) the device must be unplugged.
The system will go to “UNLOAD MODE” and the engine speed will idle down to
base idle.
Press the “ENTER” button.
The Display Box will indicate “STOPPING” and the system will shut down in approximately 25 seconds.
Turn the ignition key to “OFF”.

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Cold or Hot Weather Operation
Cold Weather Operation
In extreme cold weather, the Cat MF Cold Climate Kit should be plugged in for up to 90 minutes prior to attempting to start the engine. This will warm the compressor oil, engine oil and engine coolant, making starting easier and reducing wear on the various components. Espar Compatible Systems
If the Cat MF is connected to a vehicle’s Espar heater system, the engine coolant will circulate and be warmed automatically.
As the Espar heating system does not warm the compressor oil, the VMAC Cold Climate Kit must be plugged in when temperatures warrant it.
While the control system will prevent the compressor, generator, and PTO from starting until the engine temperature reaches 5 °C (41 °F), the Cat C1.1 Operation and Maintenance Manual (P/N: 1930372) advises that the engine coolant must achieve a minimum operating temperature of 80 °C (176 °F) prior to increasing engine speed from VMAC base idle.
After restarting from standby, the engine coolant temperature must reach a minimum of 80 °C (176 °F) prior to engaging the compressor, PTO, or generator.
In extremely cold weather, VMAC recommends setting the “STANDBY DELAY” to “NEVER” to prevent the engine from shutting down.
Overtemperature Shutdown
If the compressor or engine gets too hot, the overtemperature circuit will disable the compressor to reduce the load on the engine and allow the coolant system to reduce temperature. If the system temperature continues to rise, the system will shut the engine down.
In the event of an overtemperature shutdown, the red LED on the display box will illuminate and the display box will show a message identifying the problem. If this problem persists, see “Diagnostics and Troubleshooting” on page 79.

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Battery Charging / Boosting and Welding
This generator has been equipped with a voltage monitoring circuit to ensure that charging/welding voltages are operating correctly for the intended process.
The order of operations for connecting batteries or moving the system into weld mode must be followed exactly or the system disables itself and the generator must be reset.
Charging / Boosting Procedure
Working near lead acid batteries is dangerous. Batteries may generate sulphuric acid and hydrogen gas during regular operation. Lead acid batteries may explode if exposed to a spark. Never attempt to jump start a frozen battery. Never overcharge a battery. Always follow safety precautions when jump starting or charging a battery, including the use of appropriate Personal Protective Equipment.
The MF jump starting feature requires that the circuit being jumped has a battery installed. Do not attempt to jump start the vehicle with the MF connected directly to the starter.
Do not leave the MF connected and charging at over 30% for more than 10 minutes. Extended high voltage / current charging can damage batteries.

The MF offers battery jump starting capability up to 300 A.

Prior to charging or boosting, ensure the MF is not running, and the booster
cables are disconnected from the battery to be charged.
Set the “WELD” selection knob to 0 V. Start the MF. Engage the generator via the toggle switch located at the display box. The voltmeter should read approximately 0 V.
If “ErX” is displayed:
Ensure the booster cables are not shorted together, or connected to the
batteries to be charged, and the “WELD” selection knob is set to “0”.
Press and hold the “RESET” button for 2 seconds. Connect the positive clamp to the positive terminal on the battery. Connect the negative clamp to a good ground (ideally on the engine).
Observe the battery voltage using the Voltmeter.
12 V systems should indicate battery voltage above 2.0 V. 24 V systems should indicate battery voltage above 14.0 V.

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If the battery voltage is below the above values, the generator will not recognize the target and will not unlock the appropriate charge modes.
If the battery voltage is too low,.
Disconnect the battery from all loads. This may allow the battery voltage to
rise high enough to be recognized by the system.
If the battery does not recover adequate voltage after being disconnected,
battery detection can be temporarily over-ridden by pressing and holding both the “RESET” and “BATTERY INTERLOCK” button for 5 seconds.
Once switched into charge mode, the system will re-enable battery detection after 60 seconds.
With the battery connected, rotate the “WELD” selection knob to the
appropriate charge mode.
*The voltage should rise as the system begins charging. Set the “WELDING CURRENT” knob to 100%. Let the batteries charge for at least 5 minutes. Try starting the vehicle.
While the MF can provide up to 300 A of start assist, vehicle starters can draw upwards of 1,200 A while starting. If the vehicle fails to start, allow it to charge for longer before attempting to start again.
Return the “WELD” selection knob to 0 V.
For a list of Welder Control Box error messages and troubleshooting steps, see page 82.

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Welding
This generator has been equipped with a voltage monitoring circuit to ensure that welding voltages are operating correctly for the intended process.
The order of operations for moving the system into weld mode must be followed exactly or the system disables itself and the generator must be reset.
Welding Procedure
Plugging the optional Current Control Pendant (P/N: A500018) into the Remote Generator Control Box prior to entering “WELD” mode will cause an error.
Prior to starting the MF, set the “WELD” selection knob to 0 V. Start the MF. Engage the generator via the toggle switch located at the display box. The voltmeter should read approximately 0 V. If “ErX” is displayed: Ensure the weld cables are not shorted together, or connected to the batteries
to be charged, and the “WELD” selection knob is set to “0”.
Press and hold the “RESET” button for 2 seconds. Press and hold the “WELD INTERLOCK” button while rotating the “WELD”
selection knob to “WELD”.
If using the optional Current Control Pendant (P/N: A500018), plug it into the
Remote Generator Control Box.
Adjust the “WELDING CURRENT” and “ARC FORCE” as required. Once welding is complete:
If using the Current Control Pendant, disconnect it. Set the “WELD” selection knob to 0 V (The “WELD INTERLOCK” button is
not required when returning the “WELD” selection knob to 0 V).
For a list of Welder Control Box error messages and troubleshooting steps, see page 82.

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Getting Started Guide
Read the warnings listed on page 44 prior to proceeding.

· Ensure boost cables are disconnected from all loads &
accessories are unplugged
· Start Multifunction · Genset Switch ON

Refer to warnings on pg.8 of installation manual before use

WELD
Ensure Weld/Charge Selection Knob set to
“0V” position
While pressing “WELD INTERLOCK” button, move weld/charge selection
knob to “WELD” position

12V BOOST

24V BOOST

Ensure Weld/Charge Selection Knob set to
“0V” position
Connect boost cables to 12V battery

INFO
“ERROR 1” occurs when battery
voltage is less than 2V for 12V battery or less than 14V for
24V battery

Ensure Weld/Charge Selection Knob set to
“0V” position
Connect boost cables to 24V battery

Verify output voltage on display

Move Weld/Charge Selection Knob to
“12V” position

ERROR 1?

Move Weld/Charge Selection Knob to
“24V” position

Ready to weld

Verify output voltage on display

TEMPORARY BATTERY DETECT OVERRIDE

Verify output voltage on display

Ready to boost 12V

Move Weld/Charge Selection Knob to
“0V” position

Ready to boost 24V

Press & Hold “RESET” button for 2
seconds
Disconnect all accessories from remote weld box
Disconnect boost cables from all loads
Move Weld/Charge Selection Knob to
“0V” position
ERROR?

Disconnect boost cables from all loads
Disconnect all accessories from remote weld box
Press & Hold “RESET” button for 2
seconds
Connect boost cables to 12V or 24V battery
Press & hold both “WELD INTERLOCK” & “RESET” buttons for 5
seconds
Move Weld/Charge Selection Knob to “12V” or “24V” position, depending on connected
battery

System will boost for 60s and re-measure
battery voltage

REV005
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INFO If battery voltage is still too low after 60s of boost, the system will detect an error
and the override process must be repeated until battery voltage is greater than 2V for 12V battery or greater than 14V for
24V battery
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Diagnostics Mode

Diagnostics Mode provides access to various features such as error logs, user adjustable settings, and service logs.
Entering DIAGNOSTICS mode
· Turn the key switch to the “RUN” position but do not start the system. · Once the system has completed its self diagnostics, press and hold the “”
and “” buttons for 5 seconds to enter the diagnostic mode.
· Cycle through the menus using the “” and “” buttons.
The system will slowly scroll through menu headings.
Entering a submenu When the desired submenu is displayed:
· Press the “ENTER” button.
Scrolling While in a submenu, scroll through the data and variables using the “” and “” buttons.
Making a selection To accept a parameter, press the “ENTER” button.
Exiting a submenu To exit a submenu, press the “” button to return to the previous submenu.
Exiting DIAGNOSTICS mode Repeatedly press the “” button until “SYSTEM READY” is displayed on the Display Box.
Submenus
Once in the Diagnostics menu, there are (×5) submenus.
“USER SETUP”
This submenu contains all of the adjustable parameters.
“SERVICING”
Clears the compressor service message and records the system hours when the last 10 system service reminders where cleared.
If the display has been showing a compressor service reminder, enter this section and clear the message once the service has been completed.
“VIEW LOGGED ERRORS”
Lists the 10 most recent system errors. See page 80 for a list of error messages.
“VIEW LOGGED MESSAGES”
Lists the 10 most recent system messages. See page 85 for a list of warning messages.
“VIEW LOGGED SERVICES”
Lists the 10 most recent services logged.

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Adjustable Parameters (User Setup)

Parameter SYSTEM PRESSURE

Description Operating system pressure.

Adjustment 80 psi — 150 psi (5 psi increments).

Default Value 150 psi.

Parameter

Description

Adjustment

UNLOAD DELAY

Used to adjust the time delay before system changes from “RUNNING” state to “UNLOAD” state.

0.5 min, 1 min, 2 min, 5 min, 10 min, 15 min, 30 min, never.

Default Value 1 min.

Parameter STANDBY
DELAY

Description Used to adjust the time delay
before the system changes from “UNLOAD” to “STANDBY”
state (engine shuts down).

Adjustment 1 min, 2 min, 5 min, 10 min, 15 min, 30 min,
never.

Default Value 5 min.

Parameter TOP-UP PSI

Description

Adjustment

psi drop below system pressure before the inlet will open to build air before the engine increases to its second speed. This prevents the engine from cycling between high and low rpm to maintain full system pressure and compensates for small drops in pressure (minor leaks at quick couplings, etc.)

1 psi — 15 psi (1 psi increments).

Default Value
10 psi (System will engage compressor at 140 psi).

Parameter HIGH AIR RATE

Description

Adjustment

Measures the air use over time (psi/second). This
parameter allows the system to potentially respond to high air use before system pressure
drops below the “RESTART PRESSURE”. This is useful for tools that use large volumes of air and will allow the system to start generating air before the air stored in the receiver tank
is consumed.

0 psi — -30 psi (0.5 psi increments.) (A system with a small receiver tank combined with a high cfm tool will have a higher “air
rate”).

Default Value -3.0 psi/sec.

Parameter RESTART PRESSURE

Description The pressure at which the system will restart the engine from “STANDBY”.

Adjustment 80 psi — 150 psi (5 psi increments).

Default Value 120 psi.

Parameter COLD ENGINE RESTART

Description Allows the engine to restart if the engine begins to reach freezing temperatures.

Adjustment Enabled Disabled.

Default Value Enabled.

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Parameter DISABLE AUTO RESTART

Description Disables the system from restarting from “STANDBY” after the configured time (behaves like turning the key to “OFF”). Key switch must be turned to “OFF”, then back to “ON” to restart the system.

Adjustment

Default Value

Always, 30 min, 60 min, 120 min, never.

60 min.

Parameter LOW BATT RESTART

Description Allow the system to restart from “STANDBY” if the battery voltage drops below the configured value.

Adjustment Enabled Disabled.

Default Value Enabled.

Parameter BATT LOWER THRSH

Description The engine will restart if the battery voltage drops below the configured value for 30 seconds.

Adjustment 10.0 V — 14.0 V (0.1 V increments).

Default Value 12.1 V.

Parameter
BATT UPPER THRSH

Description
After a low battery restart, the engine will run until the battery voltage is above the “upper threshold”.

Adjustment
10.0 V — 15.0 V (0.1 V increments).

Default Value
12.8 V.

Parameter

Description

Adjustment

Default Value

LOW BATT RESTART DELAY

Delay before the countdown to “UNLOAD” / “STANDBY” starts.

1 min, 2 min, 5 min, 10 min, 15 min, 30 min.(A 2 minute delay should be adequate for standalone systems. If the Cat MF is connected to the vehicle’s batteries, a setting of 5 minutes or more should be used).

2 min.

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General Maintenance Information

The Cat MF must be run for a minimum of 30 minutes (continuous) at least once every 30 days to prevent impact damage and premature bearing failure in the compressor, due to vibration.
Regularly running the system will also help to vaporize and exhaust any water that has condensed and accumulated in the AOST.
Routine Maintenance
In order to maintain the VMAC warranty, VMAC’s maintenance schedule must be followed. Only genuine VMAC parts can be used to maintain the system.
With proper maintenance, the likelihood of premature failure or component replacement can be drastically reduced.
The most critical aspect of maintenance is proper air filtration and clean oil. If any particles enter the compressor, they can score the rotors and contaminate the roller bearings in the compressor. Any contamination will cause rapid and severe damage to components.
Torque Specifications
All fasteners must be torqued to specifications. Use manufacturers’ torque values for OEM fasteners.
The torque values supplied in Table 2 are intended for VMAC supplied components, or for use as a guide in the absence of a torque value provided by an OEM.

Apply Loctite 242 (blue) to all fasteners (except nylon lock nuts) unless otherwise stated.

Torque values are with Loctite applied unless otherwise specified.

Standard Grade 8 National Coarse Thread

Size (in)

1/4 5/16 3/8 7/16 1/2 9/16 5/8 3/4

Foot pounds (ft·lb) 9 18 35 55 80 110 170 280

Newton meter (N·m) 12 24 47 74 108 149 230 379

Standard Grade 8 National Fine Thread

Size (in)

3/8

7/16

1/2

5/8

3/4

Foot pounds (ft·lb)

40

60

90

180

320

Newton meter (N·m) 54

81

122

244

434

Metric Class 10.9

Size (mm)

M6

M8

M10 M12 M14 M16

Foot pounds (ft·lb) 4.5

19

41

69

104

174

Newton meter (N·m) 6

25

55

93

141

236

Table 2 — Torque Table

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Installation Manuals and Illustrated Parts Lists (IPL)
The installation manual and illustrated parts list are an invaluable resource for when inspecting, diagnosing or repairing the system. The installation manuals and IPL’s are available free of charge from VMAC.
VMAC Installation Manuals
https://www.vmacair.com/support/manuals/
VMAC IPLs
https://www.vmacair.com/support/ipl/

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Maintenance and Repair Safety
Prior to performing any service, ensure the vehicle is parked on level ground and that the transmission is in “PARK” with the parking brake applied and the wheels chocked (if applicable).
It is impossible to warn of all the possible hazards that may result from operating, servicing, or repairing this system. Wear all appropriate Personal Protective Equipment and follow all industry standard safety practices.
Confirm that the system is shutdown (not in “STANDBY”) with the key in the “OFF” position, depressurized and has cooled prior to performing any service work.
Never use flammable solvents to clean any components. If a flammable solvent has been used, rinse the component thoroughly with water and dry it before reinstalling it to prevent the possibility of explosion.
Use only genuine VMAC parts to maintain the system. Genuine VMAC parts are designed to work with the high pressure and heat generated by the compressor. Substituting genuine VMAC parts may void the warranty and could cause equipment damage, injury, or death.
This information is intended for people with mechanical trade certification who have the tools and equipment to properly and safely perform the service or repair. Do not attempt to service or repair this system without the appropriate mechanical training, knowledge and experience. Follow all safety precautions and industry standard “best practices”.
Safety Check List
Open the ball valve or connect an air tool to the system to ensure all of the
stored air is released.
Gently pull up on the ring, on the pressure relief valve (located inside the
service panel), to confirm the system is depressurized.
Disconnect the negative battery terminal.
Do not use the pressure relief valve as a means of depressurizing the compressor system. Doing so will prematurely wear the internal spring or the seat, preventing the valve from maintaining normal system pressure.

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Maintenance Schedule
The Cat engine maintenance schedule must be observed in order to maintain the Cat engine warranty (administered by Cat). Refer to the Cat C1.1 Operation and Maintenance Manual (P/N:1930372) for the complete engine maintenance schedule and instructions.
In the event of a warranty claim, VMAC or Cat may request service records.
The Cat MF control system records the engine and compressor hours separately. A service reminder indicating which type of service is upcoming will scroll on the display box before the service is due.
· Compressor: 10 hours before service is due, · Engine: 2 hours before service is due).
Compressor Maintenance Schedule
The following maintenance schedule must be observed to maintain both the VMAC “Standard” and “Lifetime” warranties. Regular maintenance also ensures proper performance and a long service life of the system. Service should be performed at the lesser of the two intervals (whichever occurs first). To order service kits, see the ordering information on page 10.
In order to maintain the warranty on the Cat MF, use only genuine VMAC replacement parts to service the system.

500 Hour / 6 Month Compressor Service Kit P/N: A500210

· Change the oil filter. · Change the air filter.

· Change the compressor oil.

1,000 Hour / 1 Year Compressor Service Kit P/N: A500211

· Change the oil filter. · Change the air filter.

· Change the compressor oil. · Change the coalescing filter.

Table 3 — Compressor service intervals

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Regular Inspection Instructions
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
The VMAC supplied and approved compressor oil must be used in this system. Failure to use this special oil will result in damage to the compressor and will void warranty.
Do not overfill the system. Overfilling the system with oil can flood the sight glass window and make the system appear empty.
Inspecting and Adding Compressor Oil
Ensure the unit is level and that the compressor system is depressurized and
cool to the touch.
Check the oil level in the sight glass and ensure that it is between the “MAX”
arrow and the “ADD” arrow. If the level is below the “ADD” arrow, perform the following steps:
Remove the fill cap (Figure 20). Using a funnel, pour oil into the fill fitting until the oil level in the sight glass
reaches the “MAX” arrow.
Replace the fill cap and tighten securely.

Oil fill cap

Oil sight glass

Figure 20 — Inspecting the compressor oil

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Inspecting and Replacing the Blowdown Muffler
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53).
Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
Visually inspect the blowdown muffler for evidence of corrosion or loss of functionality. Ensure the muffler allows the system to depressurize. To test the blowdown system and muffler:
Turn the system on and allow it reach full system pressure (factory setting
150 psi).
Turn off the system. Listen for the pressurized air to blowdown through the muffler on the
compressor inlet. Blowdown should be completed in approximately 20 seconds.
If the muffler is showing signs of blockage, contact a local VMAC dealer for a
replacement.

Blowdown muffler (behind discharge hose)

Figure 21 — Blowdown muffler

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Replacing the Compressor Air Filter
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
To avoid any possibility of contamination, ensure the air inlet is covered with masking tape or a clean cloth whenever the air filter cover is removed.
Do not attempt to clean the filter element, or use compressed air to perform any tasks around the compressor until the filter and cover are replaced.
Clean any loose debris from around the air filter housing to prevent
contaminants from entering the system.
Remove the filter cover and the filter element. Immediately cover the air inlet opening with a clean cloth or masking tape to
prevent contaminants from entering the system.
Clean the inside of the filter cover with a clean, dry cloth. Remove the cloth or masking tape from the air inlet and install the new air filter
element.
Ensure the filter element fits securely onto the filter plate “step” (Figure 22). Replace the air filter cover.
The compressor air filter can be accessed and changed from the service panel side of the Cat MF. For clarity, Figure 22 is shown from the radiator side of the system.
Filter plate “step”

Figure 22 — Install air filter element

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Inspecting and Replacing the Pressure Relief Valve
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
Do not use the pressure relief valve as a means of releasing pressure from the system. Doing so will prematurely wear the internal spring or the seat, preventing the valve from maintaining normal system pressure.
Visually inspect the valve and ensure it is not corroded and that the vent holes
are not plugged.
Turn the system on and allow it to reach full system pressure (factory setting
150 psi).
Ensure that air does not leak out of the valve. Air leaking from the pressure
relief valve when system pressure is at or below 175 psi indicates that the spring or seat in the valve is worn and the valve must be replaced.
If the pressure relief valve is showing loss of functionality, contact a local VMAC
dealer for a replacement.
While the pressure relief valve can be accessed and changed from the service panel side of the Cat MF, removing the top panel will provide the easiest access.
200 psi pressure relief
valve

Radiator fill door (for reference only)

Figure 23 — Pressure relief valve

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Inspecting the Engine Oil
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
Refer to the Cat C1.1 Operation and Maintenance Manual (P/N: 1930372) for the proper procedure to check the Cat MF engine oil and the oil specifications.
The engine oil dipstick is located behind the access door on the air discharge side of the unit (Figure 24).

Oil dipstick Figure 24 — Inspecting the engine oil

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Inspecting the Engine Coolant
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices. Refer to the Cat C1.1 Operation and Maintenance Manual (P/N: 1930372) for the proper procedure to check the Cat MF engine coolant, and the coolant specifications.
The engine coolant can be checked from the service panel side of the system
via the graduated coolant overflow bottle (Figure 25).
Coolant overflow bottle

Figure 25 — Inspecting the engine coolant

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Inspecting the Drive Belt
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53).
Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
Check the Front End Accessory Drive (FEAD) belt for evidence of glazing, cracks, missing or damaged ribs or damage to the belt edges and surface. If the FEAD belt is damaged, install a new FEAD belt. Inspect the pulley(s), idler(s), and tensioner for damage. If any of the components show cracks, chipping, impact damage or any other indications of physical damage, replace the component. If the damage indicates possible misalignment, check the pulley/idler/tensioner alignment. If the pulleys are not properly aligned, check all fasteners to ensure that they are properly torqued and that there are no loose or worn components. See the system specific Illustrated Parts List (IPL) for VMAC supplied part numbers.
VMAC Belt Routing

Figure 26 — Belt routing

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General Service Information

Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53).
Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
If the system is cold, bring the engine to operating temperature and then
operate the compressor system for a few minutes to bring the compressor oil to operating temperature. Warming the system will improve oil flow and will allow the oil to flow better and will also help to suspend contaminants in the oil, so that they can be removed from the system with the old oil.
Shut the compressor down. Shutdown the engine. Ensure the system is fully depressurized prior to beginning any service work. Observe all safety procedures relating to moving belts, hot oil and compressed
air. Use all appropriate Personal Protective Equipment and follow all industry standard safety practices.
Check the old oil for any evidence of metal filings or contamination. If any metal
filings are found, flush the hoses and the AOST using the VMAC flushing kit (P/N: A700214).
Push-To-Connect Fittings (Figure 27)
Lubricate the tube and firmly push it into the fitting so that the tube fully seats
in the fitting.
Slide the collet out, away from the body of the fitting to lock the tubing in
place.

Cut the tube square. Do not use side cutters as they will deform the tube

Slide the collet out once the tube is fully inserted

O-ring

Figure 27 — Push-to-connect fittings

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500 Hour / 6 Month Service (Compressor)
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices. Do not use compressed air or perform any other tasks around the air filter and cover until both are replaced. Never clean the filter element with compressed air as this may allow contaminants to enter the compressor system. Always replace the air filter element during this service.
Do not overfill the system. Overfilling the system with oil can flood the sight glass window and make the system appear empty.
A clean engine and generator compartment, in addition to being more efficient, makes detecting issues (i.e. oil or coolant leaks, etc.) easier. VMAC recommends cleaning the Cat MF as part of regular servicing.
Clean the area around the Air Oil Separation Tank (AOST) and the oil filter to
prevent contamination.
Place appropriate absorbent material under the filter to collect oil spills. Remove the oil drain plug and drain the oil into a container with a capacity of at
least 1.6 USG (6 L) (Figure 28).
Oil filter
Compressor oil drain plug

Figure 28 — Compressor oil filter
Install and tighten the oil drain plug. Remove the oil filter (Figure 28). Ensure the threaded nipple did not unscrew with the oil filter.

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*If the nipple came out with the oil filter, remove it from the filter, being careful
to avoid damaging the threads (Figure 29).

Oil filter nipple (Insert shorter threaded end into AOST)

Inspect sealing surface

Figure 29 — Compressor oil filter
*To reinstall the nipple, thoroughly clean the threads and apply Loctite 242 (blue)
to the end with the short threads and replace it in the AOST (Figure 29).
Clean the gasket sealing surface on the front of the AOST and inspect it for
damage. The surface must be free of old gasket material, and smooth, to ensure a good seal (Figure 29).
Apply a thin coat of compressor oil to the rubber gasket on the oil filter. Spin the filter onto the threaded nipple until the gasket contacts the sealing
surface on the tank, then tighten the filter an additional 3/4 to 1 turn to seat the gasket.
Remove the oil fill cap (Figure 30).
Oil fill cap

Oil sight glass

Figure 30 — Fill oil

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Using a funnel, pour oil into the fill fitting until the oil level in the sight glass
reaches the “MAX” arrow. The air compressor system holds approximately 1 USG (4 L) of oil.
Check the oil level in the sight glass on the front of the AOST. Continue adding
oil until the level is correct.
Replace the oil fill cap and tighten securely. Clean any loose debris from around the air filter housing to prevent
contaminants from entering the system.
Remove the filter cover and the filter element.
The compressor air filter can be accessed and changed from the service panel side of the Cat MF. For clarity, Figure 31 is shown from the radiator side of the system.
Filter plate “step”

Figure 31 — Install air filter element
Immediately cover the air inlet opening with a clean cloth or masking tape to
prevent contaminants from entering the system.
Clean the inside of the filter cover with a clean, dry cloth. Remove the cloth or masking tape from the air inlet and install the new air filter
element.
Ensure the filter element fits securely onto the filter plate “step” (Figure 31). Replace the air filter cover. Inspect the FEAD belt for signs of wear. Inspect all wire harnesses for signs of wear. If signs of wear are present, apply
protective loom as necessary and secure with rubber coated P-clips or cable ties.
Inspect all hoses for signs of wear. If signs of wear are present, take
appropriate action to prevent further wear.

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Connect the negative battery terminal.
Start the system and check for oil leaks. Allow the system to build to full system pressure (factory setting 150 psi). Turn the system “OFF”. Once the system has sat for 5 minutes, check the oil level in the sight glass and
add oil as necessary.
Verify there are no oil leaks.
Clearing Service Reminders
For systems that show a message “HRSxxx500HRSVC” on the control box:
Turn the key switch to the “ON” position but do not start the system. Once the system has completed its self diagnostics, press and hold the “” and
“” buttons for 5 seconds to enter the diagnostic mode.
Cycle through the menus using the “” button; once “SERVICING” is displayed,
press the “ENTER” button.
Press the “ENTER” button again to log the service.

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1,000 Hour / 1 Year Service (Compressor)
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices. Do not use compressed air or perform any other tasks around the air filter and cover until both are replaced. Never clean the filter element with compressed air as this may allow contaminants to enter the compressor system. Always replace the air filter element during this service.
Do not overfill the system. Overfilling the system with oil can flood the sight glass window and make the system appear empty.
A clean engine and generator compartment, in addition to being more efficient, makes detecting issues (i.e. oil or coolant leaks, etc.) easier. VMAC recommends cleaning the Cat MF as part of regular servicing.
Clean the area around the AOST and the oil filter to prevent contamination. Place appropriate absorbent material under the filter to collect oil spills. Remove the oil drain plug and drain the oil into a container with a capacity of at
least 1.6 USG (6 L) (Figure 32).
Oil filter
Compressor oil drain plug

Figure 32 — Compressor oil filter
Install and tighten the oil drain plug. Remove the oil filter (Figure 32). Ensure the threaded nipple did not unscrew with the oil filter.

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*If the nipple came out with the oil filter, remove it from the filter, being careful
to avoid damaging the threads (Figure 33).

Oil filter nipple (Insert shorter threaded end into AOST)

Inspect sealing surface

Figure 33 — Compressor oil filter
*To reinstall the nipple, thoroughly clean the threads and apply Loctite 242 (blue)
to the end with the short threads and replace it in the AOST (Figure 33).
Clean the gasket sealing surface on the front of the AOST and inspect it for
damage. The surface must be free of old gasket material, and smooth, to ensure a good seal (Figure 33).
Apply a thin coat of compressor oil to the rubber gasket on the oil filter. Spin the filter onto the threaded nipple until the gasket contacts the sealing
surface on the tank, then tighten the filter an additional 3/4 to 1 turn to seat the gasket.
Remove the oil fill cap (Figure 34).

Oil fill cap

Oil sight glass

Figure 34 — Fill oil

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Using a funnel, pour oil into the fill fitting until the oil level in the sight glass
reaches the “MAX” arrow. The air compressor system holds approximately 1 USG (4 L) of oil.
Check the oil level in the sight glass on the front of the AOST. Continue adding
oil until the level is correct.
Replace the oil fill cap and tighten securely. Carefully slide the coolant overflow bottle up and off of its mount, and shift it
out of the way of the coalescing filter (Figure 35).

Figure 35 — Move coolant overflow bottle
Place appropriate absorbent material under the coalescing filter to collect oil
spills.

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Only use an appropriate oil filter wrench to remove the coalescing filter, punching a screwdriver (or similar object) into the side of the filter may damage the scavenge tube or screen.
Remove the coalescing filter, being careful to avoid damaging the scavenge tube
or screen (Figure 36 and Figure 37).

Figure 36 — Remove the coalescing filter
Scavenge tube

Figure 37 — Remove the coalescing filter (Viewed from the radiator side of the Cat MF)

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Ensure the scavenge screen is in place on the scavenge tube (Figure 38).
Scavenge screen

Figure 38 — Scavenge screen
Clean the gasket sealing surface on the coalescing manifold and inspect it for
damage. The surface must be free of old gasket material, and smooth, to ensure a good seal.
Apply a thin coat of compressor oil to the rubber gasket on the coalescing filter. Spin the coalescing filter onto the threaded nipple until the gasket contacts the
sealing surface on the coalescing manifold, then tighten the filter an additional 3/4 to 1 turn to seat the gasket.
Clean any loose debris from around the air filter housing to prevent
contaminants from entering the system.
Remove the air filter cover and the filter element.
The compressor air filter can be accessed and changed from the service panel side of the Cat MF. For clarity, Figure 39 is shown from the radiator side of the system.

Filter plate “step”

Figure 39 — Install air filter element

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Immediately cover the air inlet opening with a clean cloth or masking tape to
prevent contaminants from entering the system.
Clean the inside of the filter cover with a clean, dry cloth. Remove the cloth or masking tape from the air inlet and install the new air filter
element.
Ensure the filter element fits securely onto the filter plate “step” (Figure 39). Replace the air filter cover. Inspect the FEAD belt for any signs of wear. Inspect all wire harnesses for signs of wear. If signs of wear are present, apply
protective loom as necessary and secure with rubber coated P-clips or cable ties.
Inspect all hoses for signs of wear. If signs of wear are present, take
appropriate action to prevent further wear.
Connect the negative battery terminal.
Start the system and check for oil leaks. Allow the system to build to full system pressure (factory setting 150 psi). Turn the system “OFF”. Once the system has sat for 5 minutes, check the oil level in the sight glass and
add oil as necessary.
Verify there are no oil leaks.
Clearing Service Reminders
For systems that show a message “HRSxxx1000HRSVC” on the control box:
Turn the key switch to the “ON” position but do not start the system. Once the system has completed its self diagnostics, press and hold the “” and
“” buttons for 5 seconds to enter the diagnostic mode.
Cycle through the menus using the “” button; once “SERVICING” is displayed,
press the “ENTER” button.
Press the “ENTER” button again to log the service.

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500 Hour / 1 Year Service (Engine)
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53).
Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
The 500 hour / 1 year Cat C1.1 Engine Service Kit (P/N: A500209) is intended to provide the components required to perform a basic engine service. These instructions are not comprehensive and are intended to supplement the Cat C1.1 Operation and Maintenance Manual (P/N: 1930372).
See the Cat C1.1 Operation and Maintenance Manual for a complete list of maintenance recommendations and the service interval.
A clean engine and generator compartment, in addition to being more efficient, make detecting issues (i.e. oil or coolant leaks, etc.) easier. VMAC recommends cleaning the Cat MF as part of regular servicing.
Turn the fuel supply valve to the “OFF” position (Figure 40).

Fuel shutoff valve

Oil filter (for reference)

Figure 40 — Fuel shutoff valve

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Clean the area around the primary fuel filter to prevent contamination. Place a suitable container under the fuel filter bowl to catch any fuel that may
spill.
Remove the fuel filter bowl (Figure 41).
Fuel filter base

Fuel filter bowl
Figure 41 — Remove fuel filter
Remove the fuel filter element from the filter base. Install the new fuel filter onto the filter base. Lubricate the O-ring with clean engine oil.
Do not fill the filter bowl with fuel prior to reinstalling the bowl.
Reinstall the fuel filter bowl onto the fuel filter base.
The location of the inline fuel filter will vary and is dependent upon whether the Cat MF is connected to the vehicle’s fuel tank or is drawing from the optional 7 gallon fuel tank (P/N: A500013).
Place appropriate absorbent material under the in-line fuel filter to collect any
spills.
Replace the inline fuel filter. Clean the area around the oil drain and the oil filter to prevent contamination.

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Place appropriate absorbent material under the oil filter and oil drain to collect
any spills.
Remove the oil drain plug and drain the oil into a container with a capacity of
at least 1.6 USG (6 L) (Figure 42).

Engine oil drain plug
Figure 42 — Drain oil
Replace the oil drain plug. Remove the engine oil filter (Figure 43).

Remove oil filter

Oil dipstick

Figure 43 — Engine oil filter
Clean the oil filter sealing surface of the engine block. Apply a thin film of clean oil to the oil filter gasket.

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Do not fill the oil filter with oil prior to installing it on the engine.
Thread the new oil filter onto the engine until the gasket contacts the engine. Rotate the oil filter an additional 3/4 of a turn. Remove the top panel of the Cat MF (Figure 44).
Remove top panel

Figure 44 — Remove top panel
Remove the oil fill cap, and using a funnel, add 1 USG (3.78 L) of VMAC supplied
oil into the crankcase (Figure 45).

Oil fill cap

Additional oil fill (Below muffler)

Figure 45 — Add engine oil

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Rotate the air filter cover clockwise until the locks disengage, then remove the
cover (Figure 46).
Figure 46 — Remove air filter cover
Remove the air filter and cover the engine intake with a clean cloth (Figure 47).

Figure 47 — Remove air filter

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Using a clean cloth, clean the inside of the air filter housing. Remove the clean cloth covering the engine intake and install the new air filter. Install the air filter cover, rotating it counterclockwise to lock it into position. Perform all of the additional inspections listed in the Cat C1.1 Operation and
Maintenance Manual (P/N: 1930372).
Inspect the FEAD belt for any signs of wear. Inspect all wire harnesses for any signs of wear. If signs of wear are present,
apply protective loom as necessary and secure with rubber coated P-clips or cable ties.
Inspect all hoses for any signs of wear. If signs of wear are present, take
appropriate action to prevent further wear.
Connect the negative battery terminal. With the fuel “OFF”, crank the engine for 15 seconds and immediately turn the
key switch to “OFF” (this prevents crankcase bearing damage).
Turn the fuel supply valve to “ON”.
Prime the Fuel System:
Turn the key switch to the “ON” position for 2 minutes. Turn the key switch to the “OFF” position. Turn the key switch to the “ON” position. Start the engine and allow it to run at base rpm for 2 minutes to ensure the
lubrication system and the filter are filled.
Stop the engine and allow it to sit for a minimum of 10 minutes to allow the oil
to settle.
Check the oil level on the engine oil dipstick and add oil as necessary to ensure
the level is between the “ADD” and the “FULL” marks.
Install the Cat MF top panel.
There is no way to clear the engine service reminder. Engine service reminders are displayed for 2 hours prior to the service being due, and for an additional 2 hours after the service was due.

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Diagnostics and Troubleshooting
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 53).
Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
For the following tests, isolate the AOST from all downstream (customer supplied) equipment.
If the Cat MF is still within the warranty period, see the warranty claim process on page 9 prior to commencing with any diagnostics or repairs.
If you are unsure whether the unit is still covered under warranty, contact VMAC Technical Support.
Problem diagnosis should follow sound, recognized practices. Quick and accurate diagnosis of problems should involve the following:
· Follow industry standard safety practices. · Accurately identify the problem by operating the system (provided it is safe to
do so).
· Determining the possible causes for the problem by understanding how the
system operates.
· Isolating the potential causes by accurate testing using correct and recognized
procedures.
· Performing proper repairs using the correct procedures and the recommended
replacement parts.
· Performing proper post repair testing to ensure that the repairs were effective. · Electrical testing should be performed according to the processes described
in the troubleshooting charts and in conjunction with any documentation provided by VMAC.
· Additional troubleshooting and specific test procedures can be found on
VMAC’s Knowledge Base www.kb.vamacair.com.

See “Diagnostics Mode” on page 48 for instruction to access diagnostic information.

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VMAC Error Codes

Error number

Compressor hours

Error code

(E1: Most recent error) (to 1/10 hour) (52 ENGINE RPM UNDERSPEED)

Day

Month

Year

Figure 48 — Error log display

Error Code

Display

05

COMP TEMP SENSOR FAILED ­ OPEN

06

COMP TEMP SENSOR FAILED ­ SHORT

07

COMP TOO COLD xx.x°F/xx.x°C

08

COMP OVER TEMP xx.x°F/xx.x°C

11

MANIFOLD ERROR CHECK COALESCER

12

AIR PRESS SIGNAL VOLTAGE LOW

13

AIR PRESS SIGNAL VOLTAGE HIGH

Fault Compressor temperature probe disconnected or failed. Compressor temperature probe wires shorted or failed. The compressor temperature is below 5 °C (41 °F).
The compressor temperature is above
138 °C (280 °F).
Restriction detected at the coalescing filter. The voltage signal from the air pressure sensor is below the expected value. The voltage signal from the air pressure sensor is above the expected value.

Possible Problem(s) / Solution(s)
· Test temperature sensor. · Repair wiring to sensor.
Repair wiring to sensor.
Allow the system to warm up; once the compressor temperature reaches 5 °C (41 °F) the compressor will start. · Low compressor oil level. · Faulty or crushed cooler hoses. · Cooling fan not operating. · Insufficient air-flow or
ventilation. · Failed temperature probe or
faulty electrical connection. · Incorrect compressor oil used. See “Compressor is getting too hot and is shutting down.” on page 88. Coalescing filter plugged or sensor is faulty.
· Pressure sensor faulty. · Wiring to pressure sensor faulty.
· Pressure sensor faulty. · Wiring to pressure sensor faulty.

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Error Code
14
27
34
35 36 37 38 39 40
42 51 52 — —

Display AIR PRESS SENSOR
TOO HIGH AIR PRESSURE
×××.× PSI UNEXPECTED ENGINE OPERATION
ENGINE RPM NOT DETECTED
ENGINE CRANK TIME OUT
ENGINE OIL LOW
ENGINE TEMP PROBE OPEN
ENGINE TEMP PROBE SHORT
ENGINE TEMP TOO COLD TO START
ENGINE OVER TEMP
FUEL LEVEL LOW PLEASE RE-FILL (Optional external fuel tank only) ENGINE OVERSPEED
ENGINE RPM UNDERSPEED DISPLAY CANBUS CONN ERROR END OF ERRORS RETRY STARTING?

Fault Air pressure is too high to start the engine (air pressure is displayed). Rpm detected during an
“OFF” state.
The engine did not start during the crank cycle.
The engine did not start during the crank cycle. Engine oil pressure is low. Engine temperature probe disconnected or failed. Engine temperature probe
wires shorted. Engine temperature is below -40 °C (-40 °F).
The engine is above 110 °C (230 °F).
Engine fuel level is low. Engine speed above 4,200 rpm detected.
Engine speed fell below 2,000 rpm for 3 seconds. CAN bus error between the Display Box and the
Control Box. All errors have been
reviewed.

Possible Problem(s) / Solution(s)
Blowdown not working. · Check blowdown muffler (see
page 56). · Test blowdown solenoid.
· Engine runaway due to combustible air.
· Test stop solenoid. · Stop circuit fault.
Engine rpm not detected. Engine stopped unexpectedly. · Tach wire from hall effect sensor
cut or damaged. · Hall effect sensor on bellhousing
faulty or out of adjustment. · Fuel delivery issue.
· No fuel. · Too cold to start.
· Oil leak. · Lack of service. · Oil pressure switch faulty.
· Test temperature probe. · Repair wiring between probe
and Control Box.
Repair wiring to probe.
Plug the Cold Climate Kit in and allow the Cat MF to warm prior to attempting to start the engine.
· Inadequate ventilation. · Loose fan belt. · Lack of service. · Coolant leak. · Radiator fins plugged.
Fill fuel tank prior to attempting to restart the engine.
Ensure engine high idle is within spec.
Engine speed below 2,000 rpm for 3 seconds.
Check harness running between Control Box and Display Box.
Press “ENTER” button to start CAT MF.

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Weld Control Box Error Messages
If the voltmeter detects a voltage or state that is not permitted, an error will be displayed on the screen.
If an error is displayed:
Disconnect the target battery and ensure the booster, or weld cables are not
shorted together.
Return the “WELD” selection knob to 0 V. Press and hold the “RESET” button for 2 seconds. If the error persists, contact VMAC for support.

Error
Er 0
Er 1
Er 2
Er 3 Er 4 Er 5 Er 6

Description

Corrective Action

Voltage detected above bounds for selected mode.

MF output voltage is greater than 20 V (12 V boost mode) or 38 V (24 V boost mode). · Reset system and re-attempt boost procedure. · Contact Technical Support. · Remote Current Control Pendant plugged in prior
to setting “WELD” mode (see page 46).

Voltage detected under bounds for selected mode.

Target battery is less than 2 V (12 V boost mode) or 14 V (24 V boost mode).
· Check connection between MF boost cables and target battery.
· Charge target battery in override mode to allow battery voltage to rise high enough to be recognized by system.
· Target battery float voltage is too low to be charged.

Reverse polarity detected.

Reverse polarity of connection from MF boost cables to target battery.
· Check connection between MF boost cables and target battery. Verify correct polarity (+ to + and – to -).

Incorrect mode detected.

Incorrect charge mode selected for detected target battery voltage.
· WELD INTERLOCK button not pressed while entering WELD mode.
· System not started in 0 V mode, Refer to page 46.
· Select correct charge mode according to target battery voltage.

Multifunction battery low.

MF battery voltage less than 9.0 V. · Inspect cables/connections to MF battery. · Service/replace MF alternator.

Multifunction battery high.

MF battery voltage greater than 16.0 V. · Service/replace MF alternator.

MCU Reset.

· Inspect wiring harness for damage, short/open circuit.
· Contact VMAC Technical Support.

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Engine Error Codes
The following information is an excerpt from the engine manufacturer’s manual and is copied with permission. This information is correct as of 25 January 2019 but is subject to change without notice.

Figure 49 — Engine flash codes

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Figure 50 — Engine flash codes

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Warning Messages

The messages below may be displayed in both the “SYSTEM READY” and “SYSTEM RUNNING” states.
If a message is present, the red “WARNING” LED will flash on and off.

Error Code

Display

Fault

Possible Problem(s) / Solution(s)

AIR FILTER 29
PLUGGED

Air filter is restricted.

Check air filter and replace as necessary.

32

BATTERY VOLTAGE Battery voltage below

TOO LOW

11.9 V.

· Low battery automatic restart disabled.
· System left in standby with low battery automatic restart disabled.

ENGINE RESTART 46
DUE TO COLD

The engine was restarted as the internal temperature dropped below the threshold.

Engine will restart to prevent it from freezing. Once the engine has reached operating temperature, the system will enter standby mode and shut down.

500HR / 6MTH — SERV DUE IN ××
HOURS

N/A.

This warning will be displayed 10 hours before the 500 hour / 6 month service is due.

COMPRESSOR 54 SERV 500HR /
6MTH
1000HR / 12MTH — SERV DUE IN ××
HOURS

The compressor system is due for service. N/A.

Perform 500 hour / 6 month service. Service reminder must be cleared via the “Diagnostics” menu (this also logs the service).
This warning will be displayed 10 hours before the 1,000 hour / 12 month service is due.

COMPRESSOR 55 SERV 1000HR /
12MTH

The compressor system is due for service.

Perform 1,000 hour / 12 month service. Service reminder must be cleared via the Diagnostics menu (this also logs the service).

ENGINE SERVICE —
500 HOURS

The engine is due for service.

Perform 500 hour service. (Engine service reminders do not need to be cleared).

58

ENGINE RESTART DUE TO LOW BATT

Battery voltage below restart threshold for 30 seconds.

Engine will restart to charge the battery. Once upper battery voltage threshold is reached and the battery restart delay timer has counted down, the system will enter standby mode and shut down.

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Symptoms

The following diagnostic tables are not exhaustive, they are intended to provide basic troubleshooting steps to resolve common errors. Further, or more in depth information may be posted on VMAC’s Knowledge Base: kb.vmacair.com.
If the information provided in these tables does not resolve the issue, contact the VMAC Technical Support team at: Toll free: 888-241-2289 Email: tech@vmacair.com

Key Temperatures
Engine is too cold to start: -40 °C (-40 °F) and below The engine is too cold. Plug the VMAC Cold Climate Kit in to warm the engine.
Engine is too cold to engage compressor, PTO, or generator 5 °C (41 °F) and below Allow the engine to run until it reaches operating temperature.
Over temperature shutdown
· Once the engine coolant reaches 108 °C (226 °F), the compressor, generator,
and PTO will automatically shutdown to reduce load on the engine.
· Once the engine coolant reaches 110 °C (230 °F), the engine will shut down. · Once the compressor oil reaches 143 °C (290 °F), the compressor clutch will be
disengaged.

Symptom

Possible Cause

Corrective Action

No power to Display Box.

Display Box harness disconnected or damaged. Poor connection at Display Box harness connector.

· Check display box connection.
· Check harness for damage.
Check pins in harness plug to ensure they are fully seated.

Symptom PASS System not shutting down engine.

Possible Cause PASS harness damaged or poor connection. PASS controller or switch damaged.
PASS valve faulty or dirty.

Corrective Action
Check harness connections at PASS test/trip switch and PASS controller.
Check continuity on black and blue wires on trip/test switch. · Continuity: Replace PASS
controller. · No continuity: Replace
PASS switch assembly.
Disconnect trip/test switch and check continuity between black and green wires on switch. If there is continuity, clean or replace PASS valve.

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Symptom Engine will not start.
Symptom
Low air pressure.
Symptom Compressor not building any air.
Symptom Water in the air stream.

Possible Cause System in STANDBY. Battery is discharged.
Fuel delivery issue.
PASS installed valve closed. No power to key switch.

Corrective Action
· Use stored air. · Engage generator. · Engage PTO.
Check battery voltage and charge as necessary.
· Check fuel level in the tank (vehicle’s fuel tank or optional 7 gallon tank).
· Perform fuel prime instructions (page 22).
Check PASS system for proper operation.
Check voltage at key switch.

Possible Cause

Corrective Action

Air receiver tank drain open. Close air receiver tank drain.

Air filter and/or air inlet obstructed.

Clean air inlet / replace air filter.

Air leak.

Check air hoses and fittings for damage or wear.

Air demand too high.

· Reduce air consumption. · Install air receiver tank (see
page 102).

Blowdown system stuck open.

Check for air venting from the blowdown muffler while the system is running (page 56).

Air solenoid failure.

Check air solenoid and wiring.

Pressure sensor faulty.

Test pressure sensor.

System not properly grounded.

Tighten ground connections.

Inlet valve will not open completely.

Replace inlet valve.

Possible Cause

Corrective Action

Compressor clutch worn or contaminated.

Replace clutch.

Inadequate FEAD belt tension.

Replace tensioner.

FEAD belt failed.

Replace FEAD belt.

Compressor inlet not opening. Test air solenoid.

Possible Cause Filter/Regulator/Lubricator failure (if installed). Air receiver tank not drained regularly (if installed).

Corrective Action Check drain on filter. Drain air receiver tank daily.

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Symptom

Possible Cause

Corrective Action

Low compressor oil.

· Add oil as necessary (page 55).
Refer to “Excessive oil in the air stream (oil carry over) ” on page 89 to troubleshoot.

Compressor oil flow restricted.

· Check oil filter for blockage.
· Remove hoses and check for blockage.
· Check cooler for blockage.

Compressor is getting too hot and is shutting down.

Insufficient air-flow or ventilation.

· Ensure cooler and air filter are not blocked.
· Pull out drawer (if installed in an enclosure).
· Improve ventilation. · Move Cat MF out of
cabinet.

Failed temperature probe or bad electrical connection.

Check temperature probe and wiring connections.

Lack of compressor and / or engine service.

Service system as necessary.

Incorrect compressor oil used. Flush and service system.

Symptom Air pressure relief valve opens.

Possible Cause

Corrective Action

Compressor system pressure exceeding 200 psi.

· Install pressure gauge at AOST outlet to confirm pressure is above 200 psi.
· Check pressure sensor.

Air pressure relief valve failure (opens below 200 psi).

Replace pressure relief valve.

Unload solenoid has failed energized.

Check solenoid and wiring.

Inlet valve poppet O-ring dislodged.

Contact VMAC Technical Support.

PTFE Pressure Control tube disconnected or failed.

Check PTFE tube between air solenoid and inlet valve.

Connection to Control Box poor or faulty.

Check Control Box connectors and harness.

Symptom High compressor oil consumption.

Possible Cause

Corrective Action

Compressor, hose, fitting, or cooler oil leak.

Check system for leaks.

Compressor shaft seal leaking (Oil will leak from bottom of gear case).

Replace compressor shaft seal.

Refer to “Excessive oil in the Excessive oil in the air stream. air stream (oil carry over) ” on
page 89 to troubleshoot.

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Symptom

Possible Cause

Corrective Action

Cat MF battery charge too low.

Allow Cat MF battery to charge above 10 V dc.

No generator output. (No ac / dc output).

Engine not going to second speed (elevated rpm).

Internal generator issue.

Symptom Engine rpm not increasing to second speed.
Symptom

Possible Cause Poor connection to throttle pull relay or solenoid. Poor connection to throttle hold relay or solenoid faulty. Connection to Control Box poor or faulty.
Possible Cause

Compressor was shut down while building air.

Excessive oil in the air stream (oil carry over).

Unit operating on grade greater than 15°.
High oil level. Failed coalescing filter.

Clogged scavenge screen.

See “Engine rpm not increasing to second speed.” on page 89 See Knowledge Base article: EXT-MF-005 “TESTING MULTIFUNCTION AC AND DC CIRCUITS”.
Corrective Action Swap “pull” and “hold” relays. (For testing only! Do not run system in this configuration for more than a few seconds). Check Control Box connectors and harness.
Corrective Action Stop air demand prior to turning the compressor off and allow engine speed to drop to base idle. Level the vehicle and run the system. Oil carry over may take up to 40 minutes to dissipate. Correct oil level. Replace coalescing filter. Clean scavenge screen (page 70).

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Electrical Schematic
Scan or click on the QR code below for a high resolution version of this electrical schematic:

Figure 51 — Electrical schematic legend

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P 93 P 94

P 97 P 98

Figure 52 — Electrical schematic (page 1 of 10)

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9PP395 P 96

P 99 P 100

Figure 53 — Electrical schematic (page 2 of 10)

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P 94

0

P 97

Figure 54 — Electrical schematic (page 3 of 10)

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P 93

P 95

P 98

Figure 55 — Electrical schematic (page 4 of 10)

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P 96

P 93

P 99

Figure 56 — Electrical schematic (page 5 of 10)

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P 95

P 94

P 100

Figure 57 — Electrical schematic (page 6 of 10)

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P 93

P 98

Figure 58 — Electrical schematic (page 7 of 10)

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P 94

P 97

P 99

Figure 59 — Electrical schematic (page 8 of 10)

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P 95

P 98

P 100

Figure 60 — Electrical schematic (page 9 of 10)

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P 96

P 99

Figure 61 — Electrical schematic (page 10 of 10)

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Air Receiver Tank
This system has a built-in check valve. Pressure in the air receiver tank will not be relieved when the compressor system blows down. This is normal operation. Prior to performing any service work on the system, discharge any stored air in the air receiver tank.
The system has a built-in check valve. Use of an additional check valve is not required and may cause erratic performance.
If an air receiver tank will be used with this system, the following installation procedure must be used to prevent damage to the system.
The VMAC compressor system will automatically depressurize when shutdown. The AOST has a built in check valve that prevents blow back and moisture from the receiver tank entering the AOST. Installation of an additional check valve will cause erratic performance. While the air receiver tank can be installed at any height in relation to the AOST, the discharge hose running from the AOST must be installed as high as possible on the air receiver tank to prevent problems with condensation that may have accumulated in the receiver tank (Figure 62). Drain the condensed water from the receiver tank daily.
Install the line to the receiver tank as high as possible

Air Receiver Tank

AOST

Figure 62 — Air receiver tank

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Recommended Accessories
While the compressor system will function without the following accessories, VMAC strongly recommends their use for optimal performance.
See the “Accessory Product” section of this manual on page 103 for a list of products available for purchase through VMAC.
Receiver Tank
In order for the system to enter “Standby” mode and automatically shut down, an air receiver tank rated for 200 psi, with a minimum capacity of 5 USG, is required.
An air receiver tank provides a buffer as it gives the compressor time to react by increasing the engine speed and producing air before the tool stalls. It also has the advantage of lowering the duty cycle of the compressor system.
Pressure Gauge
While not critical to system performance, a pressure gauge is important for fine tuning the system and simplifies any potential troubleshooting. Install a 200 psi pressure gauge downstream of the air discharge valve.
Pressure Regulator and/or Lubricator or FRL
The compressor can produce air pressures up to approximately 150 psi (1035 kPa). It is the responsibility of the user to know the pressure and air flow requirements of the tools powered by the air compressor system. An appropriate air pressure regulator and lub

References

• VMAC Knowledge Base
• Find A Dealer - VMAC
• Find A Dealer - VMAC
• VMAC Support & Service Resources

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