Product Specification

Prime1 Infrared Methane Sensor CH4 Sensor Description and Operation
The Prime1 sensor uses the non-dispersive infrared method to detect the presence of hydrocarbon gases. The sensor contains an infrared radiation source, a dual element custom infrared detector, a unique optical waveguide into which gas diffuses and internal ARM7 core microprocessor based electronics to provide a voltage output which is independent of the power supply polarity. The sensors can be configured to provide a pellistor format output, typically mid supply at zero with the voltage output increasing with respect to the detector pin by 100mV at range, or a linear voltage output, typically 0.4V - 2.0V over range with respect to the negative supply pin. In addition, the output can be read and the internal configuration can be accessed by a serial communications link.

The communication link contacts are pads in the 3 pin version Prime1 and pins in the 5 pin version Prime1. The internal electronics perform all the functions of driving the optical parts of the sensor, extracting the detector signals, converting the signals to a concentration, applying temperature compensation and scaling the output.When in a pellistor configuration, the Prime1 can replace catalytic sensors in existing circuitry subject to the power supply requirements. External components will be required to meet the power supply requirement when a Prime1 is used in constant current pellistor circuitry. The Prime1 is not currently Ex approved so should be housed in a suitable Ex enclosure when used in Hazardous areas.

Prime1 Infrared Methane Sensor CH4 Sensor Features
? High Resolution of 0.01%vol for 0 - 10% vol and 0.1% vol for 10 - 100% vol
? Operates independent of supply polarity
? Pellistor mimic Bridge or linear voltage output
? Operating voltage range 3.0V - 5.0V
? Operating current 80mA typical
? Latest technology MEMS detectors
? Sensing ranges: 0-100% LEL Methane, 0-100% LEL Hydrocarbons or 0-100% Volume Methane
? Default range: High resolution 0-100% volume methane
? All metal construction with isolated housing
? Small internal volume
? Flexible electronic configuration access
? User calibration also enabled by hardware connections
? Wide operating temperature range
? Fast response
? Immunity from 'poisoning'

Prime1 Infrared Methane Sensor CH4 Sensor Specification
Unless otherwise stated all data was taken using: Supply voltage of 3.5V. Ambient temperature (between 20°C and 25°C). Ambient pressure (between 995 hPa and 1020 hPa). Gases diluted in nitrogen. Gas Flowrate 1litre/min across sensor face.