If you are using a flammable gas detector, then it is almost certainly fitted with either a catalytic bead (pellistor) or infra-red sensor. The sensor converts the combustible gas concentration into an electrical signal that the instrument can process and react accordingly. Both technologies have advantages: pellistors are relatively inexpensive and are sensitive to a broad range of flammable gases, infra-red sensors are extremely robust to environmental contamination and mechanically strong but cannot be used to detect some flammable gases like hydrogen. The choice of technology utilised has often depended on a compromise between cost and reliability.
展开▼
