Non-dispersive infrared (“NDIR”) sensors are potentially low-cost (<$100), ultra low-power (<5 mW) sensors that are designed to monitor the concentration of various gases for an extended period of time, > 10 years, on a single battery charge. NDIR sensors are using proprietary mid-IR LED-receiver pairs that are tuned to the absorption spectrum of the gas of interest. This NDIR technology has applicability to a variety of NDIR gas sensors for mobile and stationary leak detection, air quality monitoring and industrial processing.
Ultra-low-power Series 5 NDIR methane sensors developed at BAH
Ultra-low-power Series 5 NDIR methane sensor integrated with SilverSpring AMI modem. The unit is being used in ConEdison field tests on BAH sensing technology.
| Parameter | Specification |
| Sensing Gas | Methane (CH4) |
| Sensor Version | BAH-5 |
| Operating Principle | Non-dispersive infrared (NDIR) |
| Voltage, source | 3.0 – 3.5 Vdc; 3.3 Vdc typical |
| Average Current | 1 mA, typical |
| Averge Power | 3 mW, typical |
| Detection Range | 0-100%LEL or 0-100% Methane volume |
| Methane Concentration Units | %LEL (500 ppm) |
| Resolution | 1%LEL |
| Warm-up Time | 10 sec |
| Response Time (T90) | 30 sec |
| Temperature Range | -30C to 65C |
| Humidity Range | 0 to 90% RH |
| Communications | UART, logic levels on TX and RX |
| Dimensions | 45 mm diameter X 38 mm height |
The following figures show typical performance of a low-power compact methane sensor.
Response of the sensor to change of the methane concentration in air.
Dependence of the optical absorption signal on the methane concentration.