Fire Detection Devices Ltd CR-135-2CO | Conventional Heat Detector, Fixed Temperature and Rate-of-Rise, White

The prefix CR in the model number indicates that the detector is a combination Rate-of-Rise and fixed temperature,(often referred to as Dual-action), unit. The Rate-of-Rise function allows the detector to close one set and open the other set of its contacts when the temperature at the ceiling increases at a rate of 8.4 C (15 F) per minute. In most cases, the closing of one set of contacts initiates the Fire Alarm sequence. The second set of contacts is commonly used to initiate an ancillary function. The fixed temperature portion consists of a spring-loaded plunger held in place by a eutectic solder that will fuse at the specific temperature (in Fahrenheit degrees) as indicated by the Model Number i.e. 135,165, 200 and 285 deg.