Simplex 4255 Series Heat Detectors

Listed Certified Peripherals Accessories Detectors Series Automatic detection of fires Compact rugged construction Rate of Rise and Fixed Temperature of operation area of protection per unit 4255 series heat detectors are an ultra sensitive thermostat designed to automatically detect excessive heat created by a fire The compact designed units are rugged and unaffected by All metal parts are brass or aluminum and mounted on a durable mineral filled phenolic No exposed metal parts carry current Electrical are all silver clad and of ample size line terminals and wire ways are provided in base for easy and efficient installation in either wiring or concealed wiring systems Two are available Rate of Rise and Fixed and Fixed Temperature only Rate of Rise and Fixed Temperature rate of rise and fixed temperature detector is a thermostat employing two methods of detection rate of rise fixed temperature rate of rise method detects fires that grow in intensity by quickly responding to fast temperature increases The fixed method detects smoldering fires which temperatures to a high level at a slow rate by to a specific temperature setting Fixed Temperature Only fixed temperature only version is of the same size style of construction as the rate of rise and fixed version but without the rate of rise RATINGS A 6 125 V AC A 6 28V DC A 125 V DC Series Heat Detector detectors having the rate of rise principle of include an air chamber a vent and a flexible diaphragm When the unit is heated the air in chamber expands The vent permits the chamber breathe and slowly release the expanded air If a fire the air in the chamber will expand more rapidly it can be vented This causes the diaphragm to a set of silver contacts normally open to set off fire alarm The rate of rise heat detector restores to a normally open contact position when the is dissipated or remains constant heat detectors have fixed temperature principle of This consists of a phosphor bronze spring under tension by standard sprinkler fusible solder the heat detector is heated to the melting point the solder the spring releases and closes the silver normally open setting off a fire alarm The detector which operates by a fixed temperature can be recognized by a small hole in the Units operated by the fixed temperature principle be reset and must be replaced combination rate of rise and fixed temperature detectors are suitable for the majority of locations should not be mounted in line with space heater directly over stoves and ovens and other heat units These detectors are available in two temperature ratings rated at 135 57.2 are suitable for most those rated at 200 93.3 are suitable the temperature exceeds 100 37.7 but 150 65.5 for extended periods of time 200 93.3 units are particularly useful in installations which lack air conditioning 2000 Simplex International Time Equipment Co Ltd 9 00 CHART N O 57.2 R of R and Fixed 93.3 R of R and Fixed 57.2 Fixed 93.3 Fixed Area sq ft x 50 m x 15 m sq ft x 30 m2 m x 9m In most fires hazardous levels of smoke and toxic gases can build up before a heat detector would initiate alarm In cases where life safety is a factor the use of smoke detectors is recommended GUIDELINES Temperature Conditions of Heat Detectors of Operation TEMPERATURE CHANGES schoolrooms and industrial where no equipment is used could cause a ceiling temperature of 15 9.44 TEMPERATURE CHANGES directly over stoves furnaces or line with space heater blowers etc ceiling temperature will have a near or exceeding 9.44 per minute 37.8 less 37.8 65.6 37.8 less 37.8 65.6 Fixed detectors should be mounted on ceilings of the to be protected Underwriters Laboratories of allows a 50 foot 15m centre to centre for units operating on the rate of rise and temperature principles Thus one unit gives for a maximum of 2500 square feet of unrestricted floor and ceiling space with ceilings up to 75 feet 20m high For joisted use 25 foot 7.5m centres or even closer Additional units should be used where appears limited due to structural of the protected area Details Series Heat Detectors 9 00 Skymark Avenue Mississauga Ontario L4W 5K5 and Representatives Throughout the World us on the world wide web at www simplexnet com specifications and other information shown were current as of publication and are subject to change without notice Printed in Canada