Senva TGR Series sensors can be ordered as individual CO or NO2 sensors or as a combination CO/NO2 sensor in a shared enclosure. Choose up to two from a variety of refrigerant gases, combustibles, or Carbon Monoxide for a combination of air quality and toxic gas detection. The analog output model features 2 outputs that support daisy chain wiring - multiple sensors may be used in a parallel sequence (0-10V) for cost effective coverage of large areas. The unit can also act as a stand alone controller, utilizing the relay for exhaust fan operation or the output for direct control of a VFD. The BACnet/Modbus model supports BACnet MS/TP & Modbus network communication in one unit. Standard features include a programmable fan relay, LED indicators, integrated display and audible alarm.
- Monitor and alert occupants of dangerous air
- Ensure adequate air flow in occupied spaces
- Alert occupants of elevated gas levels
- Directly control exhaust fans
- Parking lot CO/NO2 combo
- Leak detection for VRV refrigerant systems
- Monitor spaces heated by gas RTUs

Power Supply |
Comms |
16-30VDC/24VAC(1), 5W max, 200mA max. |
Wiring |
Conductor |
14-24 AWG, Minimum 600V, 75oC |
Outputs (Analog) |
2 programmable outputs |
0-10V, 0-5V, and 4-20mA(2) (selectable) |
BACnet /Modbus |
Protocol RS-485 |
BACnet MS/TP, Modbus RTU, Modbus ASCII |
Trouble Relay |
Trouble Relay characteristics |
N.C. 1A@24VAC/30VDC (50/60Hz) (no mains connection) |
Alarm Relay |
Alarm relay characteristics |
N.O. 1A@24VAC/30VDC (50/60Hz) (no mains connection) |
LED |
Green, Yellow, Red |
Green = Normal, Yellow = Warning, Red = Alarm |
Audible Alarm Exposure |
85dB Piezo transducer |
30 minutes above alarm setpoint per UL2075; tamper-proof silence/reset button (menu selectable) |
CO Sensor Performance |
Type |
Electrochemical |
NO2 Sensor Performance |
Type |
Electrochemical |
Carbon Dioxide (CO2) |
Type |
Non-Dispersive Infrared (NDIR) |
Methane/Propane / Hydrogen Sensor Performance |
Type |
Catalytic |
Oxygen Sensor Performance |
Type |
Electrochemical |
H2S Sensor Performance |
Type |
Electrochemical |
Ammonia NH3 Sensor Performance |
Type |
Electrochemical |
Refrigerant Sensor Performance |
Type |
Electrochemical |
Operating Environment |
Temperature, Continuous |
-20 to 50oC (-4 to 122oF) (CO2 versions rated to -40oC) |
Enclosure |
Material |
ABS/Polycarbonate |
Agency |
Compliance |
RoHS |
(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)Extreme temperatures may affect accuracy when using 4-20mA outputs.
(3) Carbon Monoxide full scale is 1000ppm.
(4) Nitrogen Dioxide full scale is 30ppm.
(5) Accuracy of CO2 reading may be reduced at temperatures below 14ºF (-10ºC).
(6) Refrigerant sensor may only be ordered as a single element sensor. It cannot be combined with other sensors.
(7)R134A sensor is factory calibrated to R134A gas but may be used as a general purpose refrigerant sensor. Sensitivity to some other gases can be found in the installation manual. Actual response may vary depending on installation. For more accurate response to a specific gas, a unit may be field calibrated.
(8) These gases my be detected by the sensor but sensitivity curves are not available at this time.
(9) Refrigerant sensors have been tested to perform at this altitude. To maintain accuracy spec, a field calibration is recommended.
(10) It is not recommended to de-activate ABC (auto-calibration) except for continuously occupied spaces or greenhouses. Drift ratings may vary based on environment.
(11) 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.
(12) A bump test involves exposing the sensor to a reference gas and detecting the sensor’s response. If sensor response is out of accuracy range, recalibration or replacement of the sensor element may be necessary.