SENVA TG Series Toxic Gas Sensor Controller Instruction Manual

INSTALLATION INSTRUCTIONS
TG SERIES
Toxic Gas Sensor
BACnet/Modbus/Analog

PRODUCT IDENTIFICATION

*Refrigerant sensors may not be paired with CH4, C3H8, or H2
WARNING

• Use installation wires rated for 75oC and above.
• Only qualified trade installers should install, program, maintain and test system incorporated therein. Installer is responsible for compliance of all applicable codes.
• Read, understand, and follow instructions thoroughly.
• The unit and associated systems require routine test and maintenance as prescribed in the TG Series User’s Manual section ‘Periodic Test and Maintenance’
• Do not install in hazardous or classified locations.
• De-energize power supply prior to installation.
• Gas sensors should not be used as a substitute for proper installation, use, or maintenance of gas emitting equipment.
• This device is designed to detect conditions that could result in acute effects of gas exposure. It will not fully safeguard individuals with specific medical conditions. If in doubt, consult a medical practitioner.
• Conduit is prone to condensation if it passes from one temperature zone to another, such as from indoors to outdoors or from one part of a building to another. This condensation may actually drip into the sensor if mounted below, causing damage and/or poor readings. In order to prevent condensation and water egress, seal both the top and bottom of the conduit with a suitable expanding foam product (such as Polywater™ Zip seal TM ZIP- 50KIT1) to prevent warm air from entering cold conduit. Alternatively, fiberglass insulation may be inserted in the conduit between the cold and warm sections using a rigid wire or other method if both ends cannot be sealed. Sealing is the preferred method.
• Conduit air flow entering sensor may prevent sensor from reading ambient air properly, resulting in under measurement of gases. Plug sensor conduit in all installations with a foam plug or seal as noted above in order to prevent airflow from the conduit.

LIMITATION OF LIABILITY

Senna’s liability, whether in contract, in tort, under any warranty, in negligence or otherwise shall not exceed the amount of the purchase price paid by the purchaser for the product. Under no circumstances shall Senna be liable for special or consequential damages.

FEATURES

The Senva TG Series sensor is a dual-sensor toxic gas detector.
There are two versions to select from; the Analog version and the Communications version(BACnet MS/TP and Modbus RTU). Each version has Trouble and Alarm relays for controls/ indication. The Analog version has two configurable 0-5V/10V or 4-20mA analog outputs that represent gas concentrations.
The communications version has a physical RS-485 connection for communications over either BACnet MS/TP or Modbus RTU.
These sensors can be mounted in an indoor application. In addition, each sensor has the following features:
Visual/Audible Indicators – LED indicator, audible alarm.
Supports BACnet and Modbus(BACnet/Modbus Version) – TG units with output type of BACnet/Modbus supports BACnet MS/ TP and Modbus RTU.
Dual Gas Monitoring – Sensor can accommodate CO, NO2, CO2, Methane, Propane, Hydrogen, Oxygen, H2S, Ammonia, Refrigerants or any dual combination in one enclosure. Sensor can be expanded in field by adding additional elements.
*Refrigerant sensors may not be paired with CH4, C3H8, or H2

NFC Setup

To change device setting that are not available through the dip switches, download the Senna Sensors app on your mobile phone. The NFC capabilities will give you access to the internal device settings for units that do not have screens.

MOUNTING

IF MOUNTING INTO A JUNCTION BOX:

1. Remove drywall clamps by turning screw counter clockwise.

IF MOUNTING INTO DRYWALL:

1. Turn both mounting clamps all the way counter clockwise.
2. Insert into drywall cutout.
3. Turn screw clockwise to tighten drywall mounts until tight to wall.

WIRING CALL OUTS

PWR – Power
PWR – Power
GND – Common/Ground
GND – Common/Ground
TR – Trouble Relay
COM – Relay Common
AL – Alarm Relay
AL – Alarm Relay
S2 – Sensor 2 analog output
S1 – Sensor 1 analog output
GND – Common/Ground

BACnet Comms Wiring

PWR – Power
PWR – Power
GND – Common/Ground
GND – Common/Ground
TR – Trouble Relay
COM – Relay Common
AL – Alarm Relay
AL – Alarm Relay
B – -RS485(B(-))
SG – Isolated Shield Ground
A – +RS485(A(+))

ANALOG SETUP

SW2

SW1

BACNET SETUP

SW4

SW3

0(000)=9600
1(001)=19200
2(010)=38400
3(011)=57600
4(100)=76800
5(101)=115200
SW4 4-5| Data/Parity/Stp
** 0(00)=8N1
1(01)=8N2
2(10)=8O1
3(11)=8E1

DEVICE OVERVIEW

1. LED indicator
2. Buzzer
3. Sensor Element 1
4. Sensor Element 2
5. Capacitive touch button
6. Capacitive touch button

PERIODIC TEST AND MAINTENANCE

Periodic Maintenance
Though the frequency of inspection is typically affected by the operating conditions and environment (extreme temperatures, extreme humidity, exposure to contaminants, etc.), Senva recommends the following maintenance and intervals. More frequent maintenance may be required per local code by the Jurisdiction Having Authority (JHA). An accurate log of all maintenance and abnormal occurrences should be maintained for the proper service of this product
Every 6 Months

• For Methane, Propane, Hydrogen, H2S, Ammonia NH3 or refrigerants retest and recalibrate the unit using NIST traceable reference gas to ensure sensors remain accurate.
• Visually inspect to ensure optimal operating conditions (no broken pieces/components, sensor filter not blocked or discolored, visual indicators operational, etc.).
• Clean the exterior with a soft cloth to remove debris from the sensor intake ports.

Annual

• For Oxygen, CO or NO2, retest and recalibrate the unit using NIST traceable reference gas to ensure sensors remain accurate.
• For sensor replacement be sure to power down the sensor and remove element to be replaced and plug in new element in its place and then re-apply power.

Do Not

• Expose the sensor and its elements to solvents.
• Immerse the sensor into liquids.

WIRING AND INSTALLATION

1. For proper detector operation, ensure that the Senva TG is connected to a continuous source of power (not controlled by a wall switch). The TG current draw figures represent worst-case conditions and will not vary as the applied DC voltage varies. To meet  the requirements of ANSI/UL 2075, Second Edition, the TG Carbon Monoxide detector employs duplicate power leads (Red and Black) where the first pair of power leads goes into the first Carbon Monoxide detector and the second pair of power leads goes to the next detector on the loop.
2. The alarm control panel zone inputs must be terminated with end of line resistors (E.O.L.R.), which are provided with the panel.
3. The relay of the TG is a dry contact and rated at 1A, 24VAC/30VDC. It shall not be used to directly drive a fan. When connecting the units to other UL approved devices, make sure that the load does not exceed the relay’s rating.

OPERATION

The following section details factory defaults for LED function, Trouble and alarm set-points, Trouble relay and alarm status functions, and the sensor element lifetime clock. These values can be modified from their default settings via the TG Series User’s Guide.
LED Function
The LED indicators function in sync with the Trouble relay and alarm status thresholds. LED will change state if either of the gases reach their Trouble or alarm set-point.

level set-point
Red| Gas concentration level above the high level set- point

Alarm Set-points
The alarm set-points are applicable for elements populated on the board by the factory, or added in the field by the user.

CO for Fire Alarm System
The sensors shall respond with the following Carbon Monoxide concentration and time limits.

Single and multiple-station CO alarms (UL Product code: CZHF)

Concentration of CO| Maximum Alarm time response
100-5 ppm| 90 minutes (not less than 16 minutes)
200-10 ppm| 35 minutes (not less than 8 minutes)
400-20 ppm| 15 minutes (not less than 4 minutes)

Trouble Signal
During a device failure mode the N.C. Trouble relay will open and the Device LED indicator will then turn yellow and blink to indicate one of the following events:

• Removal of a sensor
• Sensor is at end of life
• The pulse check function has detected a sensor failure
• The device has lost power

WIRING EXAMPLES

Note:
Colors are shown to clarify node connections; wire color shall be determined by national and local electrical codes.

Note:
Colors are shown to clarify node connections; wire color shall be determined by national and local electrical codes.

SPECIFICATIONS

05 Is.m
Outputs (Analog)| 2 Programmable Outputs CO
Output Scaling
NO2 Output Scaling
CO2 Output Scaling
Propane/Methane/Hydrogen Output Scaling
Oxygen Output Scaling
Refrigerant Output Scaling
H2S Output Scaling
Ammonia NH3 Output Scaling
Temp Output Scaling (optional)| 0-10V (default), 0-5V, 4-20mA (selectable)
0-200ppm (default), 0-500ppm (menu selectable)
0-10ppm (default), 0-10ppm (menu selectable)
0-10,000 ppm (default), 0-10,000 ppm (menu selectable)
0-50% LEL (default), 0-50% LEL (menu selectable)
0-25% Vol (default), 0-25% Vol (menu selectable)
0-1000 ppm (default), 0-1000 ppm (menu selectable)
0-100 ppm (default), 0-100 ppm (menu selectable)
0-100 ppm (default), 0-100 ppm (menu selectable)
-20 to 85ºC
Output (BACnet/Modbus)| RS-485
Baud Rates
RS-485 Loading| BACnet MS/TP, Mod bus RTU, Modbus ASCII
9600, 19200,38400,57600, 76800, 115200
1/4 unit
Trouble Relay Alarm Relay| Trouble relay characteristics
Alarm relay characteristics| N.C. 1A@24VAC/30VDC(50/601-1z)(No Mains Connection)
N.O. 1A@24VAC/30VDC(50/60Hz)(No Mains Connection)
LED’s| Green, Yellow, Red| Green = Normal, Yellow = Relay, Red = Alarm
Audible exposure alarm| 85dB@4″Piezo transducer| 30 minutes above alarm set- point per UL2034 (menu selectable)
CO Sensor Performance(2)| Type
Accuracy
Resolution
Life expectancy
Recommended Calibration
Recommended Height 4| Electrochemical
±5% of Default Range, ± 5% of Reading Above 200ppm
1ppm
7 years
Annual
3 to 6 feet; coverage 5000-7500 sq ft.
NO2 Sensor Performance 3| Type
Accuracy
Resolution
Life expectancy
Recommended Calibration
Recommended Height| Electrochemical
±5% of Default Range, ± 5% of Reading Above 20ppm
0.1ppm
7years
Annual
3 to 6 feet; coverage 5000-7500 sq ft.
CO2 Sensor Performance| Type
Accuracy 4
Drift with ABC disabled5
Range
Response time
Sample rate
Recommended Height| Non-dispersive Infrared (NDIR)
±(30ppm +3% of reading) (400-2000ppm), @-10-50°C
±(50ppm +5% of reading) Standard (2000-5000ppm), @-10-50°C
±(50ppm+3% of reading) Dual Channel (2000-5000ppm), @-10-50°C
±(100ppm+10% of reading) (5000-10000ppm), @ 0-50C
35ppm/month (6) (Standard) 5ppm/month (6) (Dual Channel)
0-2000/5000ppm; Programmable up to 10,000ppm
30s
1s
3 to 6 feet; coverage 5000-7500 sq ft.

1. One side of transformer secondary is connected to signal common. Dedicated transformer is recommended. No mains circuit connection allowed. In addition, it is required to use an isolated power supply that is certified by a national or international standard (i.e. UL). Use of a Class 2 LPS power supply or greater is required.
2. Carbon Monoxide full scale is 1000 ppm.
3. Nitrogen Dioxide full scale is 30 ppm.
4. Accuracy of CO2 reading may be reduced at temperatures below 14ºF (-10oC).
5. It is not recommended to de-activate ABC (auto-calibration) except for continuously occupied spaces or greenhouses. Drift ratings may vary based on environment.
   Methane/Propane/ Hydrogen Sensor Performance| Type
   Detection Range
   Accuracy
   Resolution
   Life expectancy
   Recommended Calibration
   Recommended Height (6)| Catalytic
   0-50% LEL (Lower Explosive Limit)
   ±5% of Range
   1% LEL
   5years
   6 months
   Hydrogen/Methane: 0.5 to 1 foot from ceiling; coverage 5000-7500 sq ft
   ---|---|---
   Oxygen Sensor Performance| Type
   Detection Range
   Accuracy
   Resolution
   Life expectancy
   Recommended Calibration
   Recommended Height| Electrochemical
   0-25% Volume
   ±5% of Range
   0.1%
   5 years
   Annual
   3 to 6 feet; coverage 5000-7500 sq ft.
   H2S Sensor Performance| Type
   Detection Range
   Accuracy
   Resolution
   Life expectancy
   Recommended Calibration
   Recommended Height| Electrochemical
   0-100 ppm
   ±5% of Range
   1 ppm
   5 years
   6 months
   3 to 6 feet; coverage 5000-7500 sq ft.
   Ammonia NH3 Sensor Performance| Type
   Detection Range
   Accuracy
   Resolution
   Life expectancy
   Recommended Calibration
   Recommended Height| Electrochemical
   0-100 ppm
   ±5% of Range
   0.1 ppm
   5 years
   6 months
   0.5 to 1 foot from ceiling; coverage 5000-7500 sq ft.
   Refrigerant Sensors Performance| Type
   Detection Range
   Resolution
   R22, R134A, R410A, R404A, R407C
   R134A Sensitivity(7)
   Life expectancy
   Recommended Calibration
   Recommended Height| MOS
   0-1000 ppm
   1 ppm
   Calibrated for respective gas
   @300ppm test gas: 450 ppm R410A, 425 ppm R407C, 400 ppm R404A, 370 ppm R22, 300 ppm R134A
   10 years (typical expectation for MOS sensors)
   6 months
   6 inches above floor; no more than 18 inches above lowest level of equipment location for leak detection; coverage 5000-7500 sqft.
   Operating Environment| Temperature, continuous
   Humidity
   Max Elevation| -20 to 50°C
   15-90% continuous, 0-99% intermittent
   2000m
   Enclosure| Material
   Rating
   Dimensions| ABS/Polycarbonate
   IP20
   5.66”h x 3.0”w x 1.69”d
   Agency| Compliance| CE
6. Combination CO/Methane, CO/Propane, or CO/Refrigerant sensors should be mounted according to Propane/Methane/Refrigerant recommendations. Consult factory for other combinations. Mounting height recommendations may be adjusted according to installation. Ensure sensor is accessible for maintenance and target gas has unobstructed access to sensor. Mount in accordance with ANSI/NFPA 70 and NEC or CEC.
7. R134A sensor may be used as a general purpose refrigerant detection. The sensor’s response to other refrigerants will change proportionally as shown in the following app note:  https://www.senvainc.com/catalog/documents/downloadcenter/Refrigerant%20cross%20sensitivities.pdf (or scan QR code). Actual response may vary depending on installation. For more accurate response to a specific gas, a unit may be field calibrated.

https://www.senvainc.com/catalog/documents/downloadcenter/Refrigerant%20cross%20sensitivities.pdf

TROUBLESHOOTING

to prevent drafts and dilution during test.

BACnet/Modbus Quick Reference

The following section outlines some commonly utilized Modbus registers and BACnet objects for quick reference. For a complete list and description of each, please see the associated protocol guides: TG BACnet Protocol Guide or TG Modbus
Protocol Guide.
Access Legend:
R=Readable
W-Write-able
W0 = Write-able with 0 only
NV = Saved in non-volatile configuration memory

Description| BACnet Object| Modbus Register| Access
---|---|---|---
Gas 1 Concentration| AI1| 6/7| R/W0
Gas 2 Concentration| AI2| 8/9| R/W0
Gas 1 Warning Set-point| AV1| 101| R/W/NV
Gas 1 Alarm Set-point| AV2| 102| R/W/NV
Gas 2 Warning Set-point| AV4| 104| R/W/NV
Gas 2 Alarm Set-point| AV5| 105| R/W/NV

Supported Modbus Functions:
0x03 Read Multiple Holding Registers
0x04 Read Register Input
0x06 Write Single Register
0x10 Write multiple Registers

DIMENSIONS

Revised 3/15/2021 Document #152-0386-0AO
senvainc.com 1-866-660-8864
1825 NW 167th Place
Beaverton Oregon 97006

References

• Senva inc: Gas Sensors, Toxic Sensors, Dry Pressure Sensors, Wet Pressure Sensors, Humidity/Temp Sensors, Current Switches, Current Transducers, Energy Measurement, Relays, Leak Detection, IoT Solutions, Smart Sensors

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