Wiring ESL 449CSTE Smoke detector to ELK M1?


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I am having a difficult time wiring the 4 wire ESL smoke detector 449CSTE (with relay) to the ELK M1. The enclosed file is basically the only document to deal with the 449 CSTE. The ELK reports Fire Trouble - an open circuit. I connected a 2200 ohm resistor to the connections in the diagram indicated as End of Line Device. The device is the only device on Zone 1. Not sure where to go from here.


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If you place the end-of-line resistor between terminals 6 and 7 (counting from + power as terminal 1) does that clear the trouble? This is the same as putting the resistor across the zone with no detectors attached. If the trouble does not clear then go back to the panel, disconnect the detectors and put the resistor across the zone with nothing else attached.

If the first step fixes it, the issue is with the detector connections or detector itself.

If the second step fixes it, you have a problem someplace along your cable run.

If neither fixes it, there is a problem with the panel configuration for the zone.
The supervisory relay is terminals 9,10,11 counting from the first + as 1 with 9-10 indicated as open and 10-11 as closed. Where does this relay connect to? The diagram shows 6 connecting to 10 and 8 connecting to 11 that puts the relay on the alarm circuit and not the power circuit. Is this correct?
Yes, that is correct. Since the relay is built into the detector, the coil of the relay is internally attached to the power terminals so the relay is energized whenever the detector has power. The relay contacts are supposed to go in series with the end-of-line resistor on the alarm circuit so that the zone only sees the resistor if the relay is powered and the contacts are closed.

If power fails, the alarm circuit no longer sees the resistor and reports a zone trouble. If the detector sees smoke it shorts the alarm circuit triggering a zone alarm condition.

Another test you can do is to verify that the two contacts in the diagram are closed when there is power on the detector using an ohm meter. If they mistakenly referenced the contacts that are closed when power is NOT on the detector in their diagram then you would get a trouble on the zone. (The trouble would go away if you removed power on the detector.)
Let me see if I understand this. The alarm circuit going to the M1 zone is in parallel with the resistor and relay - the resistor and relay are in series. The alarm circuit is usually open. The relay has power when the device has power so it is normally closed. That allows current to flow through he resistor and is picked up by the Elk as device ready. When the device trips, it shorts the alarm circuit so that more current flows through the short setting off the alarm. If power is lost to the device, the relay opens thus creating an open circuit that is picked up by the M1 as device trouble.
OK, now of the 11 terminals, which gets connected to which? 5 & 6 seem to be one side of the alarm circuit, while 7 & 8 are the other side of the alarm circuit. If the relay were not involved I could see putting the resistor between 6 & 7 and connecting the M1 zone wires to 5 & 8. That would put the resistor in parallel with the M1 zone wires.
Since the relay and the resistor need to be in series, I would think the resistor needs to go from 6 to 10 and then a wire from 11 (relay closed) back to 7 to complete the parallel resistor-relay circuit. Is it possible to damage the M1 if the detector wires are screwed up?
You are correct in your understanding. Don't confuse a tempory troubleshooting hookup (6 &7) to bypass the relay and verify the panel and wire run, with the operational hookup that includes the relay.

The first step is to confirm that the zone works correctly with the resistor. After you get the trouble to clear that way, you can introduce the relay contacts. It could be something as simple as the contact designations being wrong in the diagram (this is where the meter test helps).
OK It works without the relay wired in. Wow, I'm starting to understand this stuff! Scary! The status shows 7.1 volts. Now to wire in the relay! I assume I wire in the relay as closed - terminals #10 and #11.