What component is key in the normal operation of the thermocouple fire detection system?

The bimetallic thermoswitch is crucial to the operation of thermocouple fire detection systems. This component functions by responding to temperature changes; it consists of two different metals that expand at different rates when heated. When a fire occurs and the temperature rises, the differential expansion causes the bimetallic element to bend or flex, which can then trigger an alarm or other safety response in the fire detection system.

In the context of thermocouples, which operate based on the principle of measuring voltage changes associated with temperature gradients, the bimetallic thermoswitch serves as an important relay to process the thermal signals effectively. This allows for reliable detection of fire by ensuring that the system can quickly and accurately respond to dangerous temperature increases, which are indicative of a fire event.

Other components, like heat-sensitive cables or continuous loop sensors, may play roles in different types of fire detection systems but are not foundational to the specific operation of typical thermocouple systems. A pressure gauge is unrelated to the functionality of fire detection and is not involved in the thermal measurement process.