Omni pro using 2 wire smokes
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pete_c
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I think you could run autonomous 2-wire zones wiring them separately to 1-4 on the panel. Here did the 4-wire zone thing and it was a pita to do that and have individual zones.
Here have an HAI diagram inside of the door of the HAI can that shows the basic 2-4 wiring schema.
I think it is different between the Elk panel and the HAI panel.
Here is an Elk wiring schema description between using 2-wire and 4 wire from here:
Since 2-wire smokes are powered by the alarm zone, I do believe you are constrained to fewer detectors on one zone.
Elk only puts out 40ma per zone (if memory serves me). Zone 16 might be different (the preferred smoke detector zone), but I don't think so.
Electrically, I am not certain how a 2-wire detector could have a sounder on the unit since it shorts when alarmed. A sounder would have resistance and thus prevent the panel from seeing short. Maybe there is a trick I am not aware of.
As far as the panel is concerned, it sees short when alarmed and responds the same.
I installed 4-wire units in my house and have never played with 2-wire models. The added work of installing the extra 2 wires is insignificant. Elk automatically takes care of the power reset feature. You don't have to have the supervising relay at the end, but I recommend you do (code might say you have to have it). Again, it adds about 30 seconds more work screwing down the extra wires.
As far as using the relay on the 4WTAR-B unit, I do believe the relay closes not when alarmed but when powered up. This is a supervising relay, not an alarming relay.
4-Wire HAI diagram:
Del's response to diagram above:
@ Pete:
You don't technically "need" a reversing relay, but in order for a tandem ring to happen and it be coded, you either need to reverse the polarity to the smokes AND provide a temp-3 pulse to the smokes or use a reversing relay. For those that question this as "legal" it is because the host system components (relay boards, etc) are listed for fire alarm service...I used to do it this way when I worked for another company that didn't have reversing relays that functioned properly with the host panel (ESL relay).
DSC's unit is bass-ackwards. DSC panels work off a switched negative, contrary to almost every other panel in the world (barring those that are installed in the EU).
Here have an HAI diagram inside of the door of the HAI can that shows the basic 2-4 wiring schema.
I think it is different between the Elk panel and the HAI panel.
Here is an Elk wiring schema description between using 2-wire and 4 wire from here:
Since 2-wire smokes are powered by the alarm zone, I do believe you are constrained to fewer detectors on one zone.
Elk only puts out 40ma per zone (if memory serves me). Zone 16 might be different (the preferred smoke detector zone), but I don't think so.
Electrically, I am not certain how a 2-wire detector could have a sounder on the unit since it shorts when alarmed. A sounder would have resistance and thus prevent the panel from seeing short. Maybe there is a trick I am not aware of.
As far as the panel is concerned, it sees short when alarmed and responds the same.
I installed 4-wire units in my house and have never played with 2-wire models. The added work of installing the extra 2 wires is insignificant. Elk automatically takes care of the power reset feature. You don't have to have the supervising relay at the end, but I recommend you do (code might say you have to have it). Again, it adds about 30 seconds more work screwing down the extra wires.
As far as using the relay on the 4WTAR-B unit, I do believe the relay closes not when alarmed but when powered up. This is a supervising relay, not an alarming relay.
4-Wire HAI diagram:
Del's response to diagram above:
@ Pete:
You don't technically "need" a reversing relay, but in order for a tandem ring to happen and it be coded, you either need to reverse the polarity to the smokes AND provide a temp-3 pulse to the smokes or use a reversing relay. For those that question this as "legal" it is because the host system components (relay boards, etc) are listed for fire alarm service...I used to do it this way when I worked for another company that didn't have reversing relays that functioned properly with the host panel (ESL relay).
DSC's unit is bass-ackwards. DSC panels work off a switched negative, contrary to almost every other panel in the world (barring those that are installed in the EU).
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