Wiring / Connecting 2 Wire and 4 Wire Smoke Detectors to an Alarm System

Wiring / Connecting 2 Wire and 4 Wire Smoke Detectors to an Alarm System

We are often asked how to connect low voltage smoke detectors to a wired alarm system.  First we need to point out that smoke detectors are a life safety product and so it's critical that you read and understand how the connection should work, and hire a pro if needed.  You will also need to test the after installation and regularly thereafter to ensure they are working.

There are two types of low voltage smoke detectors: 2 wire and 4 wire smoke detectors.  A 2 wire smoke detector will typically connect to a special two wire FIRE zone on the panel with only 2 wires.  Multiple smoke detectors can be connected.  A 4 wire smoke detector can typically connect to any wired zone, and the zone needs to be specified in panel programming as a fire zone.  More often, each 4-wire detector goes on its own zone, which aids in determining exactly which detector was triggered, but it's possible to connect more than one.

Also  an EOL (end of line) resistor is normally required to be installed at the - end of the line at the (last) smoke detector.  An end of line relay may also be required to supervise power on a 4 wire connection.

Again, if in doubt please hire a pro to make sure it's done safely.. it's there to protect your life & property after all.  We will not provide detailed instructions beyond this basic information.  We recommend this work to be completed by a pro.



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