Honeywell 20P Programing Hardwire Type for Smoke and CO Detectors

Old 07-08-18, 04:30 PM
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Honeywell 20P Programing Hardwire Type for Smoke and CO Detectors

Do I use Hardwire type as 0 (EOL) or 2 (NO) for 4 wire smoke and CO detectors with a Honeywell 20P panel on zone 2 and 3?

I know that both Smoke Detectors and CO Detectors are NO, and they use the EOL resistors to be Supervised. When programming the zone in a Honeywell 20P panel, I am using a zone type 9 for the 4 wire smoke detector and a zone type 14 for the CO detector, but do I use a Hardwire type as 0 (EOL) or 2 (NO)? I assume it should be 0 - EOL since I have a resistor across the Detector to ensure it is supervised, but I want to make sure I have the correct Hardwire Type, as I don't want the sensor to go off and short the connect and have the panel show it as a "trouble" instead of an issue.
Old 07-08-18, 07:47 PM
Join Date: Nov 2009
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Fpadar, the answer is the same now as it was on your earlier thread a few days ago:

Smoke Detector and CO zones are _always_ programmed as Hardwire Type 0, EOL.

In the context of Hardwire Type programming, "NO" refers to zones that are not supervised, i.e, no EOL Resistor. Fire and CO zones ALWAYS have an EOLR, i.e., are ALWAYS supervised.

The 4-wire smoke sensor zone is supposed to short out the EOLR: That's what makes the panel see an alarm. An Open (e.g. severed or disconnected wire) will generate a Trouble condition. A short on a Fire Zone signals an alarm.

There is nothing technically wrong with shorting zones 2 through 8: The outputs are current-limited and shorting won't damage anything. Only Zone 1 shouldn't be shorted because it carries a power supply on the zone loop, therefore can't be current limited like the other on-board zones.

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