Hydrogen sulfide gas detector with humidity and temperature compensation

A system for monitoring a gas concentration of hydrogen sulfide, the system comprising:

• a gas detector further comprising:
• a metal oxide semiconductor-based gas sensor having an electrical characteristic that changes based on the is related to the hydrogen sulfide concentration and a temperature, the and a sensitivity to moisture;
• measurement circuitry coupled to the metal oxide semiconductor-based gas sensor programmed to measure the electrical characteristic;
• a controller, coupled to the measurement circuitry programmed to generate a non-compensated hydrogen sulfide concentration output based on the measured electrical characteristic;
• and
• a communication circuitry, coupled to the controller, that communicates on a process communication loop and provides the non-compensated gas concentration output to a process controller;
• a humidity measurement system, located remotely from the gas detector, that samples ambient air, obtains the ambient humidity, and communicates the ambient humidity over the process communication loop to the gas detector;
• a temperature measurement system, located remotely from the gas detector, that accesses the ambient air, obtains the ambient temperature, and communicates the indication over the process communication loop to the gas detector;
• and
• wherein the controller is programmed to calculate a compensated hydrogen sulfide gas concentration, that compensates for effects of ambient humidity and ambient temperature on the non-compensated hydrogen sulfide gas concentration output, by applying the ambient temperature, the ambient humidity, and solid state sensor resistance to a compensation equation, and generates a compensated hydrogen sulfide concentration output that is proportional to the square root of the ambient humidity based on the compensated hydrogen gas concentration.