Fire detection Devices LLC
CR 135° - 165° - 200° EWT & CF 135° - 165° - 200° EWT Explosion proof heat detectors
The EWT Series of THERMOFLEX™ heat detectors for fire alarm systems are Explosion proof, Weather proof, Water-tight and Dust-tight.
With its non-metallic diaphragm, the detector can operate normally at low temperatures, making it suitable for non-heated, exposed or chilled spaces including garages, boat decks, engine rooms, tunnels, etc., or in corossive or high humity environments.
Class I, Group C - atmospheres containing ethyl ether vapours, ethylene, cyclopropane
Class I, Group D - atmospheres containing gasoline, hexane, naphtha, benzene, butane, propane, alcohol, acetone, lacquer solvent vapours, or natural gas.
Class II, Group E - atmospheres containing metal dust, including aluminum magnesium and their commercial alloys, and other metals of similarly hazardous characteristics
Class II, Group F - atmospheres containing carbonaceous dusts including carbon black, coal or coke dust
Class III, Group G - atmospheres containing flour starch or grain dust
Class III, A location where there is a danger of explosion due to the presence of flammable fibers or flyings
Rate-of-Rise & Fixed Temperature
The Model Number prefix “CR” 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 its contacts when the temperature at the ceiling increases at a rate of 8.4 Celsius degrees (15 Fahrenheit degrees) per minute. The closure of the contacts initiates the Fire Alarm sequence. 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, and 200.