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Discussion Starter · #1 ·
Would anyone by chance have a PDF of a 2280 Fire Alarm Panel manual? I know this one was installed regularly before PDFs came around, but I'm headed out in the am to do some troubleshooting on one and not sure if a manual is on site... This one was in about 1978...

Someone was smart enough to wire the alarm contact in series with the trouble contact and put them both to a PLC input to shutdown a site... It has had a mystery intermittant PLC alarm that has seemed to clear by the time anyone gets there.. I'm guessing it is a trouble on the panel, and am going to start ripping into end devices tomorrow.. There are only a half dozen fixed heats and one EOL, so definately not an overly complicated system..

Had it have been wired the way I (and I'm sure alot of others) would have done, the PLC input would have been off the alarm only contacts, and with a phantom "alarm" and automatically resetting it would have pointed the finger at the panel.. Now with finding the trouble contacts in series, and I am 99% it is a non-latching relay, it outta get interesting tracing it out..

Seems the issues started recently, and there was some recently pulled in teck cable in the vicinity of a FA junction box (by another contractor)..
 

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Discussion Starter · #2 ·
Figured out the issues..

Went to site this morning and did some troubleshooting. Since the drawing showed 4 heat detectors and there are 7, an abandonned one, and an EOL first mission was to make a drawing... Found numerous bad connections along the way, so redid all of them. Found 2 - 4" pieces of wire spliced together to make an 8" piece for the EOL, so I replaced that. Went to the panel and couldn't read the EOL... Went to the last detector and couldn't read it there either.. Opened it up and when I went to check the factory side, one lead broke out of the end of the resistor. Had to leave it in "trouble". Tested the detectors and they all but one rang in, so removed that one and jumperred it out... Removed the fault contacts from the shutdown string to the PLC and hooked it all back up...

New detectors, and EOL on order..

Found out it wasn't a 2280 as I thought.. It is a 1527.. Recommended an upgrade to maybe something at least out of the 90s...
 

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I have on occasions where alotted outputs or inputs on the monitoring system, wired through both the alarm and trouble contacts.
It's not ideal.
I think your approach was spot on.
Is there another input for the plc to monitor facp troubles? Does the plc even need to know if the facp is in trouble?
 

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Discussion Starter · #4 ·
I have on occasions where alotted outputs or inputs on the monitoring system, wired through both the alarm and trouble contacts.
It's not ideal.
I think your approach was spot on.
Is there another input for the plc to monitor facp troubles? Does the plc even need to know if the facp is in trouble?
There's tons of extra inputs, but I doubt that they would add the trouble to an input. There are no bells, strobes, etc on the annunciating circuit from the panel.. The PLC does sound a yelper when the alarm rings in.. I think it could hold some value in that you could be losing some of your detectors in the circuit and it could alert to a potential problem. Gonna try and get them on board with changing out some heat detectors in MCC areas to smokes.. I don't know how effective a 195 degree fixed heat will be in the main MCC, but that one can't change to a smoke, but I'm trying to lobby for 2 others to go to smokes..

Up until today, one of the operators never even knew the panel existed... lol..
 
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