Heat Detector Testing

 Heat Detector Testing

Heat detector can be defined as an element or device that detects changes in heat or fire. If any heat (change in heat that exceeds the limits of heat sensor ratings) is sensed by the heat sensor, the heat sensor generates a signal for alerting or activating a security or protection system to extinguish or avoid the fire accidents. There are different types of heat sensors, which are classified based on different criteria such as the amount of heat withstanding capacity, nature of heat sensing capacity, and so on. Furthermore, the heat sensors are classified into different types that include analog heat sensors and digital heat sensors.

Heat detector can sense the heat (change in heat according to the features of heat detector used). But, a circuit is to be designed for activating an alarm system to indicate fire or heat change and for alerting the security or protection system. Heat detector circuit can be designed using heat sensor.

These heat detectors are mainly classified into two types based on their operation and they are “rate of rise heat detectors” and “fixed temperature heat detectors”.

Before starting the job, take the proper work permit and inform to all the respective departments. Then do force the respective logics or interlocks if any (like fire suppression systems activation etc).

§  Prior to testing of Heat detector see the LED status of the Heat Detector it should be blinking red.

§  Check the voltage of the Heat Detector, it should be + 30 Volts DC. This can be checked by the addressable base of the detector. (Digital type detector).

§  Now Heat Detector is healthy and it is ready for testing.

§  Clean the Heat Detector’s dust by cotton cloth and blower

§  Apply the heat to the Heat Detector by solo heat-detecting gun.

§  Keep applying heat for 10 seconds.

§  After 10 seconds LED status of the Heat detector is changing from steady blinking red to steady red and after that alarm appears and the hooter is activated on the fire alarm panel.

§  To silence the hooter press the acknowledge key to the Fire Alarm Panel.

§  After the alarm appears remove the heat-detecting test gun from Heat Detector.

§  Note down the alarm tag and descriptions from the HMI or Graphic workstation. The alarm details must match with the heat detector tag number and installed location.

§  Confirm the heat detector activation status from the respective graphics page. You have to visually identify the colour change signals of the respective heat detector on the graphics.

§  Reset the alarm of the Heat detector from the Fire Alarm Panel.

§  The LED status is changing from steady red to blinking red.

§  Heat Detector is now working normally.

§  Repeat the above procedure for all the remaining Heat Detectors.

§  Normalize the forced interlocks or logics if any.

§  Close the work permit.

Note: The mentioned voltages, terminals, circuit module names may change as per the vendor or model of the Heat Detector. Available in both 110 / 120 and 220 / 240 volt versions the Solo 423 and 424 are the professionals’ choice where cables and leads are acceptable. Unconstrained by energy availability they provide the quickest of test times and are, perhaps, most suitable for the highest temperature detectors.