1. Thermocouple and magnetic valve composegas safety protection devices, thermocouple is a transducercan provide the power, magnetic valve is a controller.,
2. When thermocouple tips is heated by fire, cold and heat generate thermoelectric power due to temperature difference, to form closed loop current and make magneticvalve actuation,opening gas path.
3. When the flame is out owing to unexpected reasons, thermocouple rapidly lose potential, magnet valve lose suction under the action of spring, so close gas path, and play a safety protection role.