Security & Fire Protection Systems/DSC PC1550 - No Power



I have a DSC PC1550 alarm system. A month ago, the trouble light came on after I opened a door while the alarm was active. I checked the code and it was Zone 1 (battery). I took the battery out, and the system actually functioned fine for a couple of weeks, but with the trouble light still on. I finally changed the battery, and all was well for about a day, until the battery apparently ran out, which tells me that the system was running solely on it. (?)

After that, it started inadvertently alarming about every 5 minutes. I unplugged it, disconnected the wires from the transformer (Revere RT1640), re-plugged the transformer into the outlet to check the output... (18V?). Nice and warm to the touch too.

Any suggestions for actions would be MUCH appreciated.



ANSWER: Hello Mike, try this...

Disconnect both the battery and the transformer. Wait 10 minutes. Reconnect the battery, and then the transformer.

If the system alarms, try the *2 command to see if a trouble code shows, and let me know what it is.


Best Regards,


---------- FOLLOW-UP ----------


Thanks for the help!! Sorry for the delay. Other things came first! :-)

The trouble code is the same. I tried a new transformer, and a new battery. Same results. Keeps triggering the system "horn" every 3-4 minutes for about 2-3 seconds, then the keypad just goes dark and everything shuts down completely.

I'm thinking... bad board?

Thanks for the follow-up Mike.

Could you do a measurement for me? Disconnect the AC, and leave the battery plugged in. Wait about 15 minutes and then measure the voltage on the battery. If it's not right around 12 volts, I'd suspect that the charging circuit has failed, and is not charging the battery.

And while you're there, how do the plug-on connections to the battery look? Are they clean and shiny, or are they covered in gray ash? If they're covered in gray ash, you can try to clean them up by unplugging them and scrubbing with a wire brush (or even an old toothbrush).

Let me know!

Thanks, Dave

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Dave Neuweiler


The design and application of burglary and fire systems for homes and businesses. Helping alarm owners understand how their system works. Helping to troubleshoot false alarm problems. Questions about monitoring issues.


Over a quarter century in the industry. Experience in installation, service, and monitoring centers. Training manager for a national protective services company; director of education and training for a national trade organization for for alarm dealers.


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