Fire Detection

With point sensors

KIDDE-DEUGRA sensors are responsible for the fire detection:
In case of an fire or overheat the sensor sends an alarm signal to the control unit.

The control unit alarms the crew and the crew is forced to activate the fire extinguishing system.

The sensor not only alert the control unit, it also report when the temperature has dropped down below the threshold.

And: All sensors are ready again after succesful fire fighting

Electronic Point Sensors

DTF-R sensors essentially are nothing else than extremely fast-responding NTC resistors. They have an extremely robust housing to protect the sensor against water and mechanical damages.  
In practice: the software in the control unit can adjust the alarm temperature of each single sensor individually.