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    How to Use the IS Smoke Heat Combo Unit


    Does the DS284IS or D273IS photo smoke detector have a fixed temp heat sensor or rate of rise heat sensor built in?


    The D273IS and the DS284IS are both photo electric smokes with a 135° Fixed temperature heat sensor.

    *On both models, the heat sensors are isolated, this means that a heat alarm will provide a separate alarm output through one set of contacts and smoke alarm will provide an alarm output through a  second set of alarm output contacts, either smoke or heat alarm will activate the sounder circuit differently. Heat Alarm is a Steady output from the sounder and the Smoke Alarm will produce a Pulsing sounder output.

    These detectors also take separate power, which requires a D275 EOL.

    Sounder Function

    The sounder acts differently depending on what test is preformed.

    1. When sprayed using canned smoke the sounder pulseson a smoke alarm output trips.
    2. When tested using a magnet the sounder is steady and trips the isolated heat output.
    3. When tested using a heat gun the sounder is steady and trips the isolated heat output.

    *After the unit is placed in alarm using canned smoke, the sounder and latched LED will clear on its own when the chamber is free of smoke.

    10-30 VDC

    Standby - 80uA @ 12 volts 100uA max

    Alarm - 100mA +or- 10mA @ 30 VDC

    Part numbers DS284IS, D273IS

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    Last update:
    ‎05-21-2018 07:53 PM
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