TheAlarmTech.com

So I went on a recent service call for a quickstart, version 2.5 cpu in cabinet 1. There were 6 cabinets, (the main panel and 5 remote annunciators, all of them the 60 zone style (30 button type.) It was showing an ANN2 CH1 communications fault. After checking voltage at ANN2 RAI board it was showing normal, 23 VDC for power, and about .2-.4 vdc for the rs485 data. The wiring was class B and went from the main panel first to the one that was having the issue, about 20 feet away in an office. and then to the other 4. (none of which were having issues except cab2.) I checked to make sure the wiring was hooked up correctly, which it was. after talking with EST they had me check the ribbon cable from the RAI to the CPU, which I did, and replaced it with a brand new one, thinking that might be the issue, still no fix. They then had me run codeloader to the ANN2 and redownload to it, same problem. The odd thing is that none of the annunciators after it were having an issue, only this one (first one in chain.) I replaced the cpu and re downloaded to all cabinets, same issue, not sure what else to do. The main panel was displaying the same message as the annunciator, none of the others were displaying this after the redownload. At that point I ran out of time, and ended up taking it out of the program and disconnecting it. Whole system was normal at this point. After replacing ANN2 cpu, I did download all databases starting with CAB1 to CAB6, in order and all downloads were successful. Any ideas on what the issue could be?

You need to eliminate things.
is it hardware, wiring or a program problem?
I would move the troubled ANN and a good one next to the QS panel so you are working close and controlled.
switch the two ANN's address see which way the trouble goes.
I have done this a few times and it can be very helpful.
- good luck, let us know what you found

Sounds like you did everything right, you might try replacing the RAI I've had them go out before but not often, a trick an est tech told me once is to download the main panel and not leave the download page and move to the next Ann download and on down the line till all are downloaded, it didn't make sense to me but it worked also there could be another ann with the same address as 2 I've seen that also. good luck!

Ended up being a bad annunciator, can't remember which one.