HKC alarm triggering randomly

fletch

I have an old HKC SW812 alarm system. It works great however recently one zone has started to trigger in the middle of the night with the error "Alarm Gross". The zone in particular has 3 windows, all with contact sensors, no inertia sensors. Is it possible that one of the sensors is faulty now? I checked the cabling around each of the sensors and they look good. Before calling out an alarm technician, would it be a good idea to replace all the sensors (as they're so cheap)?

altor

https://www.boards.ie/discussion/2058235202/hkc-alarm-triggering-randomly

Yes it is possible something on that zone is faulty or one or more devices are.

You would need to check it with a multimeter to find the faulty device or devices.

Changing all the sensors on the zone would also hopefully solve the issue.

fletch

Thanks. I'm going to try changing the sensors myself to see if that resolves the issue. Will report back. The screws on one of the sensors are all rusty (in the en-suite) so perhaps moisture has got in.

fletch

Would these do the job?

fletch

Or these?

altor

https://www.boards.ie/discussion/comment/118711501#Comment_118711501

https://www.boards.ie/discussion/comment/118711517#Comment_118711517

https://www.boards.ie/discussion/comment/118711522#Comment_118711522

Yes, the ones with the terminals will work perfect

fletch

Old terminal were fairly rusty....replaced with new sensor...fingers crossed it sorts out the issue

altor

Perfect, hopefully that sorts the issue

fletch

Didn't sort the issue 😖 Got 2 nights without the alarm going off but last night it went off. Strangely, normally the keypad says Pulse when the alarm triggers but this time it just said Alarm. I'm going to replace the rest of the sensors on the zone and see if that fixes it. If not, I might need to call in an engineer or is there anything else I could try?

fletch

Was chatting to @davidconroy46 and he suggested putting the zone into SOAK and and by process of elimination (disconnecting each sensor), figure out exactly which sensor is the offender so I'm going to try that now.

altor

https://www.boards.ie/discussion/comment/118732229#Comment_118732229

Only way to test the sensors is with a multimeter.

If you didn't do this and are still having issues then its either the cable or another device or devices on the loop.

Changing all the devices rules out the devices.

hesker

Maybe check continuity on the cables. I had a similar issue years ago. Also had a mouse problem at the time so conclusion was that the little bugger chewed part way through a cable. Switching to a couple of unused cores within the cable solved the problem.