nVent RAYCHEM 465 Electronic Controller for Heat Tracing of Fire Protection Piping User Manual

October 31, 2023
nVent RAYCHEM

nVent RAYCHEM 465 Electronic Controller for Heat Tracing of Fire

Protection Piping

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
Piping-product

OVERVIEW

Introduction

This manual provides information pertaining to the installation, operation, testing, and maintenance of the nVent RAYCHEM 465 fire sprinkler heat trace controller. The controller is c-UL-us listed for freeze protection of fire suppression system supply piping and branch lines. Additional copies of this user manual may be ordered separately through your nVent Thermal Management representative or online at nVent.com. This document covers the 465 controller and its available options. This fire sprinkler heat trace controller is designed for the following trace heating products necessary to make up the complete freeze protection system for supply piping and branch lines including sprinkler heads: nVent RAYCHEM XL-Trace Edge cables 5XLE1-CR, 5XLE2-CR, 5XLE1-CT, 5XLE2-CT, 8XLE1-CR, 8XLE2-CR, 8XLE1-CT and 8XLE2-CT heating cables; as well as nVent RAYCHEM RayClic-PC, RayClic-PS, RayClic-PT, RayClic-T, RayClic-S, RayClic-X, RayClic-E, RayClic-LE, RayClic- SB-02, RayClic-SB-04 connection kits and accessories.

Trace Heating Systems for Fire Sprinkler Systems
The design and monitoring of trace heating systems for fire sprinkler systems shall be in accordance with IEEE 515.1. Trace heating systems for fire sprinkler systems shall be permanently connected to the power supply. If backup power is being provided for the building’s electrical systems, it shall also provide a backup power supply for the trace heating system. The thermal insulation used for the supply piping and branch lines shall be non- combustible and protected with a sealed exterior non-combustible cover that will maintain its integrity when exposed to water discharge as shown below:

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Piping-fig- \(1\)

Figure 1.1 Example of sealed exterior non-combustible cover for the pipe insulation The thermal insulation for the sprinklers shall be installed to comply with the obstruction requirements of NFPA 13 so that the thermal insulation over the trace, heating does not unacceptably obstruct the sprinkler or Cover the wrench boss. When installing the XL-Trace Edge trace heating system on branch lines with sprinkler heads follow the methods shown below:

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
Piping-fig- \(2\)

Figure 1.2 Installing XL-Trace Edge on the Sprinklers
Sprigs are typically 1-inch IPS with 0.5-inch thick thermal insulation. The insulation may be oversized to accommodate the heating cable installation, resulting in no greater than 3 3-inch installed outer diameter (OD). Typically thermal insulation of 2-inch thickness should be used on branch lines and supply piping to balance the heat loss of the system and power output of the trace heating. For upright sprinklers only, the sprinkler heads shall be insulated up to the top of the reducing bushing with a taper of 45° to avoid spray-pattern obstruction, as detailed in Figure 14 of IEEE 515.1-2012. The minimum sprinkler temperature rating shall be (155°F [68°C]).

Product Overview Description

The 465 controller monitors, controls, and communicates supervisory events and data for one heating cable circuit. The intended use of the 465 controller is to control and monitor heat tracing circuits for fire sprinkler systems. Each unit is a single-point controller with a 5″ inch color touchscreen display for intuitive setup and programming right out of the box. The 465 controller may be used with line-sensing or ambient-sensing and proportional ambient-sensing control (PASC) modes. It measures temperatures with two 2 KOhm / 77°F (25°C), 2-wire Thermistors connected directly to the unit. The controller can also measure ground fault current to ensure system integrity. If the equipment is used in a manner not specified by nVent Thermal Management the protection provided by the equipment may be impaired.

Features
A detailed description of available features may be found in Section 4 of this manual. Highlights of specific features are as follows:

Touchscreen Display
The touchscreen display provides the operator with large easy-to-read messages and prompts, eliminating complex and cryptic programming.

Single or Dual Temperature Sensor Inputs
The ability to utilize one or two temperature sensor inputs allows the selection of ambient or line sensing control modes and the programming of all temperature parameters.

High and Low Temperature
High and low-temperature supervisory events are offered for both temperature sensor inputs.

High-Temperature Cutout
A high-temperature cutout is provided for both temperature sensor inputs.

Low Current Condition
The 465 controller offers a low current condition to identify situations where the heating cable is not pulling adequate current.

Electromechanical Relay (EMR) Output
The 465 controller is equipped with a 24 A-rated electromechanical relay (EMR) output switch with device failure supervisory status change.

Ground Fault Condition and Trip
Ground fault (GF) current levels are monitored and are displayed in milliamperes (mA). The adjustable ground fault level gives the user the choice of ground fault current levels suitable for the particular installation.

proportional Ambient Sensing Control (PASC)
The 465 controller includes the Proportional Ambient Sensing Control (PASC) mode to maximize the energy efficiency of the heat tracing system.

Temperature Sensor Failure
Both open and shorted sensors are detected by the controller.

Certification
nVent Thermal Management certifies that this product met its published specifications at the time of shipment from the factory.

Limited Warranty

This nVent Thermal Management product is warranted against defects in material and workmanship for a period of 18 months from the date of installation or 24 months from the date of purchase, whichever occurs first. During the warranty period, nVent Thermal Management will, at its option, either repair or replace products that prove to be defective. For warranty service or repair, this product must be returned to a service facility designated by nVent Thermal Management. The Buyer shall prepay shipping charges to nVent Thermal Management and nVent Thermal Management shall pay shipping charges to return the product to the Buyer. However, the Buyer shall pay all shipping charges, duties, and taxes for products returned to nVent Thermal Management from another country. nVent Thermal Management warrants that the software and firmware designated by nVent Thermal Management for use with the 465 controller will execute its programming instructions properly. nVent Thermal Management does not warrant that the operation of the hardware, software, or firmware will be uninterrupted or error-free.

Warranty Exclusion/Disclaimer
The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by the Buyer, Buyer-supplied software or interfacing, unauthorized modification or misuse, operation outside of the specifications for the product, or improper installation. No other warranty is expressed or implied. nVent Thermal Management disclaims the implied warranties of merchantability and fitness for a particular purpose.

Exclusive Remedies
The remedies provided herein are the buyer’s sole and exclusive remedies. nVent Thermal Management shall not be liable for any direct, indirect, special, incidental, or consequential damages, whether based on contract, tort, or any other legal theory.

Conducted and Radiated Emissions: FCC Statement of Compliance This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a commercial/ residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

  • Reorient or relocate the receiving antenna.
  • Increase the separation between the equipment and the receiver.
  • Connect the equipment to an outlet on a circuit different from that to which the receiver is connected.
  • Consult the dealer or an experienced radio/TV technician for help.

CAUTION! Do not modify the device. Any changes or modifications made to a device that is not expressly approved by nVent could void EMC compliance. Innovation, Science, and Economic Development (ISED) Canada ICES-003 Compliance Label: CAN ICES-3 (B)/NMB-3(B)

Product ratings
Note : The 465 controller can’t monitor the load current and ground fault current in each cable segment when an external contactor is used. These Supervisory conditions are disabled when an external contactor is used.

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
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Protection-Piping-fig- \(4\)nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-
of-Fire-Protection-Piping-fig- \(5\)nVent-RAYCHEM-465-Electronic-
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\(6\)

INSTALLATION AND WIRING

Introduction
This section includes information regarding the initial inspection, preparation for use, and storage instructions for the 465 controller.
Note : If the 465 controller is used in a manner not specified by nVent Thermal Management, the protection provided by the the controller may be impaired.

Initial inspection
Inspect the shipping container for damage. If the shipping container or cushioning material is damaged, it should be kept until the contents of the shipment have been verified and the equipment has been checked mechanically and electrically. If the shipment is incomplete, there is mechanical damage, a defect, or the controller does not pass the electrical performance tests, notify the nearest nVent Thermal Management representative. If the shipping container is damaged, or the cushioning material shows signs of stress, notify the carrier as well as your nVent Thermal Management representative. Keep the shipping materials for the carrier’s inspection.

Product Contents

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Installation location
The 465 controllers standalone version is approved for the TYPE 12 protection class for indoor use. Install the controller in an indoor, dry, clean, accessible location. Make sure you install the controller within 328 ft (100 m) of where you want to monitor the pipe or ambient temperature. The ambient temperature sensor shall be installed in the location representative of the ambient temperature of the fire sprinkler system, including elevation. Considerations should include accessibility for maintenance and testing and the location of existing conduits.

Mounting procedures
The mounting steps are shown in Figure 2.1 A, B, C, and D. Drill conduit entry holes prior to mounting. Conduit entries should be made in the bottom of the enclosure if possible to reduce the possibility of water entry from condensation or leakage. Conduit entries must be drilled or punched using standard industry practices. Use bushings suitable for the environment and install them such that the completed installation remains waterproof. Grounding hubs and conductors must be installed in accordance with Article 250 of the National Electrical Code and Part I of the Canadian Electrical Code. The hubs shall be connected to the conduit before they are connected to the enclosure.

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
Piping-fig- \(8\)

Wiring
The following drawings provide sample wiring diagrams for the 465 controller and optional accessories. Grounding hubs and conductors must be installed in accordance with Article 250 of the National Electrical Code and Part I of the Canadian Electrical Code.

Power and Load Connections
The 465 controller may be powered directly from a 120 V to 277 V supply. All of the power terminals are labeled for easy identification. Do not attempt to use wire sizes that exceed the marked terminal ratings and Avoid terminating two wires on the same terminal whenever possible.
Note: Follow the industry standard grounding practices. Do not rely on conduit connections to provide a suitable ground. Grounding terminals/screws are provided for connection of system ground leads. The glands/conduits should be inserted into the metal grounding plate provided with the controller. Power wires are connected to terminals labeled L (line), N (neutral), and PE (Ground).

v

Figure 2.2 Power connection
The heating cable conductors are connected to terminals labeled L/, N/, and the braid is connected to PE.

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Piping-fig- \(11\)

Figure 2.3 Heating cable connection
Temperature Sensor and Extension Cables
The 465 controller has two (2) temperature sensor inputs. Use only 2-wire Thermistor 2 KOhm / 77°F (25°C) sensors provided. Sensor 1 should be connected to terminals S1 while Sensor 2 should be connected to terminals S2 and. The controller also operates with just one sensor.
Note: The ambient temperature sensor shall be installed in the location representative of the ambient temperature of the fire sprinkler system including elevation.

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
Piping-fig- \(12\)

Supervisory relay connections
The 465 controller includes terminals for one supervisory relay as shown in figure 2.5. It can support both AC and DC power sources (please refer to the max voltage and current specifications for the relay above). It may be wired for normally open (N.O.) or normally closed (N.C.) operation. The contractor shall connect the supervisory indicator to NO, COM to have the relay signal a supervisory condition when it’s open. In normal operation, the NO contact is closed. In case of power loss or supervisory condition, the NO contact is open. The contractor shall connect the supervisory indicator to NC, and COM to have the relay signal a supervisory condition when it’s closed. In normal operation the NC contact is open. In case of power loss or supervisory condition the NC contact is closed The supervisory relay is used to provide a supervisory signal to a fire alarm system for any of the following conditions:

  1. Ground fault current
  2. Low system temperature
  3. High system temperature
  4. Temperature sensor failure
  5. Internal error
  6. Loss of continuity
  7. Loss of incoming supply voltage

Note: The supervisory relay is intended to be used for switching low- voltage, low-current signals. Do not use this relay to directly switch line voltages.

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
Piping-fig- \(13\)

Figure 2.5 Supervisory relay wiring
After all connections are made, connect the network cable from the touchscreen to the port on the controller as shown below:

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
Piping-fig- \(14\)Close the lid with a screwdriver and turn on the circuit breaker for the circuit. The circuit breaker used for branch circuit protection should be a maximum 30 A circuit breaker. The power wires used should be of appropriate size for the current rating as per NEC/CEC.

Short Cables Length Handling
During quickstart, the controller checks the current flow after a short period of time. If the current flow is below the detection limit, the user will be asked whether the contactor mode should be activated or whether Short heating cables should be used (which deactivate the current monitoring of the output, the low current alarm will be disabled).

Initializing the controller
Initial Heating Cable Test
To minimize the risk of damage to the controller due to a heating cable fault, the integrity of the heating cable should be verified by performing the commissioning tests detailed in the appropriate product installation
and operating manual. These manuals can be found on nVent.com. These tests must be performed with the controller output disconnected. Once the cable has been checked, it may be reconnected to the controller and power applied.

CONTROLLER OPERATION
Quickstart
When the unit is powered up for the first time, a Quickstart must be executed before the unit is ready to start. The Quickstart helps to set all important settings, the unit will go in main screen mode automatically when done. Quickstart is sufficient for normal operations. More settings are available from the settings menu.

Quickstart menu
After QUICKSTART completion, the main menu screen will appear as follows

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
Piping-fig- \(15\)nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-
Protection-Piping-fig- \(17\)

Figure 3.1 Main menu screen

  1. Settings Button
  2. Application Description
  3. Firmware Version
  4. Supervisory Event Indicator
  5. Heat Cable Power Indicator (red when the cable is powered)
  6. Sensor 1 Measured Temperature
  7. Sensor 2 Measured Temperature
  8. Application Picture
  9. Control Setpoint
  10. Keylock Indicator

The Green LED will blink as follows

  • Normal operation, heater on: 1.5 sec on/0.5 sec off
  • Normal operation, heater off 1 sec on/ 1 sec off
  • Supervisory condition: 0.2 sec on/1.8 sec off
  • Press the Settings button on the Main Menu Screen to get to the Settings Menu.

Settings menu

nVent-RAYCHEM-465-Electronic-Controller-for-Heat-Tracing-of-Fire-Protection-
Piping-fig- \(19\)

The settings menu has three sections:

  1. The System section allows you to read system information, run test the program, service the system such as upgrading the firmware, export event log/energy consumption/temperatures or calibrate the screen,
    read the status of the heat tracing circuit, enable key lock, assign device ID, and reset the system to factory settings.

  2. The Heating Cable and Pipe section allows you to set circuit parameters such as control mode, set point, sensors, minimum ambient temperature, temperature conditions filters and ground fault settings.

  3. The General settings enable you to select country, language, voltage, date, time, and units. The details of each section are provided on the next page.

System menu

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Piping-fig- \(20\)

Info
Purpose General info about the unit, name, commissioning date, firmware version, nVent Thermal Management contact info per country.

Test Program
Purpose The test program runs for 30 minutes, during which all parameters will be ignored to check the heating cable and the connection on site. You can stop the test program at any time.

Service
Purpose This is a password-protected area for users to service the unit. The default password is 2017.

Sub-menu includes
Log File: Provides information about the warnings, the last event, control mode, heating cable, set point, ambient temperatures measured and time stamp.
Calibrate Screen: Press the dot to calibrate the touch screen.
USB: The USB drive can be used to upgrade the firmware, and export temperature, energy consumption, and event log data.
Energy Consumption: Displays the energy consumption chart over time.
Select Power Adjustment: For Proportional Ambient Sensing Control (PASC), the Power Adjustment Factor can be selected. The Range is from 10% to 200%. The default is 100%.

Status Purpose Displays the status and parameters for the heat tracing circuit. Displays information such as sensor 1 and sensor 2 temperatures, duty cycle, control mode, load current, GFP current and if the external contactor is connected.

Keylock Feature
Purpose When the key lock is “On”, the setup and timer menus are protected by a password. To unlock the unit, enter the predefined password (3000). The unit will automatically lock itself after 10 minutes of inactivity or when the Lock “On” key is pressed.

Factory default: Key lock is “On”
Press the down arrow key to move to the next page of the System Menu

Assign Device Number
Purpose Assign a 4-digit number to each device as an identifier for that device.

Reset
Purpose To provide a quick method of resetting the controller’s configuration parameters to the Factory Default parameters. Select “Yes” to activate the Quick Install menu and return all settings to factory settings. The quick start process restarts automatically.

Heating cable and pipe menu
Figure 3.4 Heating cable and pipe menu In this menu, every parameter line shows the actual value/attribute for each parameter.

Sensor Setup
Sensor setup allows the user full flexibility in configuring the temperature sensors as shown in Figure 3.5 below:

The 465 controller allows for two temperature sensors. Assign each sensor to be a line or ambient sensor. If both the sensors are assigned as line or ambient sensors, the controller will control based on the lower measured temperature of the two sensors. Select if you want the circuit to remain on if the given sensor fails by clicking “Power On TS Fail”. Select which sensor you would want to use for high-limit cutout. Make sure Sensor 1 is connected to terminals S1 and. For Fire Sprinkler freeze protection applications, usually, one sensor will be an ambient sensor and the second sensor will be a line sensor with high limit cutout enabled. The high-limit cutout sensor should be located where the fire sprinkler piping is expected to be the warmest. In the case of a sprinkler system with sprigs, the high-limit cutout sensor should be located on one of the sprigs. At least one sensor needs to be connected for the controller to function. The second sensor, if not connected, will be automatically disabled.
Note: The high-limit cutout sensor should be located where the fire sprinkler piping is expected to be the warmest.
Note: The “High Limit Cutout” feature turns the circuit off when the corresponding sensor reaches the high limit cutout temperature.

This feature has a higher priority over the “Power On TS Fail” feature. In other words, the circuit in high limit cutout condition will remain powered off until that condition goes away and the TS Fail condition won’t power the circuit on.

Control Mode

Purpose Sensor setup allows user full flexibility in configuring the temperature sensors as shown in figure 3.5 above: Setting Ambient On/Off Mode: The ambient sensor measures the ambient temperature. If the ambient temperature is above the setpoint temperature plus deadband, the relay output is turned off. If the ambient temperature is below the setpoint temperature, the output is turned on. Line Mode: Line sensor measures the line temperature. If the line temperature is above the setpoint temperature plus deadband, the relay output is turned off. If the line temperature is below the setpoint temperature, the output is turned on.
PASC: The ambient sensor measures the ambient temperature. The PASC algorithm auto-controls the heat output and maintains the temperature at the setpoint. The algorithm will be derived from the following of parameters:

  • Setpoint: 32°F – 104°F (default 40°F)
  • Minimum Expected Ambient Temperature: –40°F – 40°F (default 20°F)
  • Pipe Size: 0.5″ / 1″ / >2″ (default 0.5″)
  • Power Adjustment Factor: 10% – 200% (default 100%)

For more details on PASC please refer to Appendix A.
Note: The “Power On TS Fail” feature turns the circuit On if the controlling temperature sensor fails. E.g. in line sensing control mode, the “Power On TS Fail” won’t trigger for the ambient sensor failure and vice versa.

Setpoint
Purpose This is the temperature that the controller uses to determine whether its output switch should be on or off. Setting/Range 32°F to 104°F (0°C to 40°C) Factory Default 40°F (4°C)

Deadband
Purpose The deadband is a window of difference between the measured control temperature and the desired control setpoint temperature and provides the decision to turn the output off or on Setting/Range 1°F to 8°F (1°C to 4°C) Factory Default 5°F (3°C)

Minimum Expected Ambient Temperature
Purpose This is the minimum expected ambient temperature that will be used to calculate the duty cycle for proportional ambient sensing control mode Setting/Range –40°F to 40°F (–40°C to 4°C) Factory Default 20°F (–7°C)

Cable Type
Purpose Select the type of cable for the heat tracing circuit

Pipe Diameter
Purpose Select the pipe diameter for the heat tracing circuit Setting/Range 0.5 inch, 1.0 inch, 2.5+ inch Factory Default 0.5 inch

Low Temperature
Purpose This allows the user to select the low-temperature

Supervisory for both sensors
Setting/Range –40°F to 190°F (–40°C to 88°C) Factory Default 35°F (2°C)

High Temperature
Purpose This allows the user to select the low-temperature

Supervisory for both sensors
Setting/Range 32°F to 190°F (0°C to 88°C) Factory Default 110°F (43°C)

High Limit Cutout Temperature, Setpoint
Purpose Set high limit cutout temperature for the selected Sensor (in the sensor set-up). This setpoint is used to turn the circuit off when the sensor reaches the high limit cutout temperature. Setting/Range 32°F to 190°F (0°C to 88°C) Factory Default 185°F (85°C)

Temperature Condition Filter
Purpose Set time delay filter for temperature condition Setting/Range 1 to 200 seconds Factory Default 10 seconds

High Ground Fault Current
Purpose This allows the user to set the ground fault current supervisory level. Exceeding this limit will trigger the supervisory event to indicate that a ground fault condition exists in the heating cable circuit. To protect against the risk of fire or shock, the ground fault level should be set at the lowest level possible to allow the normal operation of the cable. Setting/Range 20 mA to 200 mA Factory Default 20 mA Supervisory event time delay filter is factory set as immediate

Ground Fault Trip Level (HI GF Trip)
Purpose This allows the user to set the ground fault current trip level. Exceeding this limit will result in the output switch being latched off and the ground fault level trip supervisory activated to indicate a ground fault condition. Warning: Fire Hazard. Ground fault trip supervisory must not be ignored. To prevent the risk of fire, do not re-energize heating cables until the fault is identified and corrected. Setting/Range 20 mA to 200 mA Factory Default 30 mA

General settings menu

Language
Select English or French

Country
Select USA or Canada

Date
Use the up/down arrow keys to select the year, month, and day

Time
Use the up/down arrow keys to set the hour and minute

Voltage
Select the appropriate voltage for the application

Select Unit of Measure
Select Imperial or Metric units

Time Format
Select 24H (24 hours) or 12H (12 hours) time format

Supervisory events

Filter Times

Error Codes

The followings are the error codes for different conditions and their description.

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TROUBLESHOOTING

The 465 controller may be used as an effective troubleshooting tool to pinpoint problem areas of heating cable circuits. Described below are a few of the more common problem areas, their symptoms, and parameters to check to determine the actual faulty portion of the heating cable circuit.

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Protection-Piping-fig- \(31\)

APPENDIX A: PROPORTIONAL AMBIENT

SENSING CONTROL (PASC)

PASC takes advantage of the fact that the heat loss from a pipe is proportional to the temperature difference between the pipe and the ambient air. This is true regardless of heating cable, insulation type, or pipe size. Once the heat tracing and insulation on a pipe has been designed to balance heat input with heat loss and maintain a particular temperature, the main variable in controlling the pipe temperature becomes the ambient air temperature. The 465 controller has a control algorithm that uses the measured ambient temperature, desired temperature, minimum ambient temperature assumption used during design, and size of the smallest pipe diameter to calculate how long the heating cable should be on or off to maintain a near- constant pipe temperature. The power to the heat tracing is proportioned based upon on the ambient temperature. If the ambient temperature is at or below the “minimum design ambient plus 3°F” the heating cable will be on 100%. If the measured ambient is at or above the “maintain temperature –3°F” the heating cable will be on 0%. For any measured ambient between “minimum design ambient” and “maintain temperature,” the heating cable will be on a percentage of the time equal to (maintain temperature – measured ambient) / (maintain temperature – minimum design temperature).

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The following parameters are used in calculating the duty cycle in PASC

North America
Tel +1.800.545.6258
Fax +1.800.527.5703
thermal.info@nVent.com 2023 nVent. All nVent marks and logos are owned or licensed by nVent Services GmbH or its affiliates.
All other trademarks are the property of their respective owners. nVent reserves the right to change specifications without notice. RAYCHEM-IM-H60742 -465Controller-EN-2304

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