Infrared Combustible Gas Detector 4101-28
The new IR Gas Detector is a ruggedized instrument designed specifically for monitoring methane in a range from 0-100% LEL in high-vibration environments like compressor stations. Providing an industry-standard analog 4-20 mA interface to connect into customer's PLC’s, DCS systems, or Sierra Monitor controllers. This stand-alone gas sensor module is purpose-built to meet extreme operating conditions in remote locations. Built with Sierra Monitor’s trusted and proven pedigree, and ready to manage your gas risk. This detector is fully certified to meet the stringent and code-compliant standards of UL-2075 as outlined in the International Fire Code for gas detectors.

The detector utilizes Non-Dispersive Infrared technology to monitor for combustible gases. This technology provides for a long service life and also allows the detector to rapidly recover after exposures to high concentrations of hydrocarbon gas and operate in environments where catalytic bead poisons might exist. The detector also has minimal maintenance requirements and only requires one-year calibration intervals.
The Infrared Combustible Gas Detector model 4101-28 is UL-2075 performance approved, ATEX hazardous location approved, and SIL-2 registered. These approvals and certifications assure our customers that we perform to the highest quality standards.
Ruggedized Design
Ideal for a high-vibration location like compressor stations
Analog 4-20mA output
Industry standard 3 wire analog current source
Non-intrusive Calibration
Able to calibrate module without declassifying the area
Reduced maintenance and cost of ownership
Longest rated and UL-approved calibration cycle for any infrared gas detector

Sensor |
Type: Infrared, Dual Wavelength |
Performance |
Default Range: 0-100% LEL Methane Repeatability: +/-1% LEL Accuracy: +/- 1% for 0-50% LEL range , +/- 2% for 51-100% LEL range, +/- 1% full scale per month |
Output |
Display: None Single Output: Analog 4-20 mA Linear, current source 3-wire Non-isolated |
Operating Range |
Ambient Temp Range: -40 to 1400F (-200 to 600C) Relative Humidity: 0-95% Non-Condensing |
Construction |
Dimensions: (H x W xD) Inches: 1.5 x 4.5 Weight: 7.2 lb. (3.3Kg) Enclosure: 316 Stainless Steel Housing: 316 Stainless Steel Enclosure Hazardous Area Classification: Explosion proof, Class I, Div. 1, Groups A, B, C, D Class I, Zone 1, Group IIC, IP66, IP65, NEMA 4X, T6 TA= -400C to 700C II2 GD, Ex d IIC |
Power |
Power consumption: 3-watt maximum Input voltage: 24V DC nominal: 10-30V DC |
Limited Warranty |
2 years |
Approvals |
UL-2075 ATEX II 2 G, Ex d IIB+H2 T6 Gb, Ta=-20°C to +60°C SIL-2 Certified: IEC 61508 IECEX: Certificate of Conformity |

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