How to tell if PIR is faulty?

[alan333]

Hi,
My Galaxy G2-12 has thrown 2 false alarms over the last fortnight, both on the garage PIR. There's no sign of a spider walking across it or a jacket falling off a nail etc. Do sensors just go faulty? Is there anything I can check beyond the wiring?

I have spare sensors (from changing to pet friendly ones) so it's not a big hassle to change it if it's the best option.
Thanks

 

[Europlex]

Have a look INSIDE the detector, livestock is not unheard of there.

 

[sparkymarka]

Or mice ?

 

[EightyTwo]

I have found "No More Spiders" quite useful on garage detectors (and CCTV cameras). They've changed the formula recently (dumpy bottle with a black trigger spray) with peppermint oil rather than clove(r) oil. I don't know if the new one is as effective (trialing it now...) but the old one certainly banished spiders to another corner of the garage and false alarms stopped.

It's a shame that you didn't upgrade the garage PIR to a pet-friendly. We'd never fit a regular PIR in a garage, prefering to fit a pet-friendly dual-tech. You may have furry four legged friends on a shelf/box/window sill rather than the eight legged ones!

And, in answer to your original question, yes - they do just go faulty. Old PIRs seem to get more sensitive and "trigger happy". Don't forget that power (12V) interruptions will cause the PIR to alarm too. This could happen if a mouse was eating the cable.

 

[alan333]

Thanks for the replies

I'll check for critters inside the sensor first, never thought of that. The cable is visible and untouched by rodents, and there's no cobwebs etc. It might be a pet friendly (or better?) sensor since it's different to the interior ones I changed earlier.

I'll do some more homework and report back. Thanks again.

 

[alan333]

Had a chance to check it out today. Took the cover off and found it clean inside, no sign of spiders etc anywhere. Did a walk test and although the sensor lights up as expected, it doesn't show open on the test. All other sensors show as expected. All wiring ok and connections tight. I presume I need a new sensor?

Was thinking of this Bosch tritech...
http://www.ebay.co.uk/itm/380654680828?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

Any thoughts?

 

[sparkymarka]

Nice but pricey !

 

[alan333]

You think I can get away with this one then?

http://www.ebay.co.uk/itm/380510559207?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[sparkymarka]

No stick to the tritech

 

[alan333]

No stick to the tritech

Thanks, I've ordered one

 

[alan333]

Fitted the new sensor yesterday and checked that it was in "tamper" state before fitting the cover... all good. Then I walk tested it.... Nothing. Scratched my head a lot and, to cut along story short, discovered that the walk test doesn't beep if you have the zone on soak. Turned soak off and it walk tests fine.

Just to be certain I checked the open/closed state when the OH came in. All checks out fine. I have set it on soak for a few days but all should now be well.

On the other hand my old sensor was probably on soak when I walk tested it the other day, so maybe it wasn't faulty after all. Either way something was giving false alarms so hopefully it's now cured.

If anyone intends burgling me while this zone is on soak beware of the two under-fed Rhodesian Ridgebacks, Fang and Satan, who are permanently locked in the garage. They're always pleased to see us but to be honest I don't fancy a stranger's chances.

Thanks again folks

 

[alan333]

Just an update... no false alarms since the new sensor was fitted. Thanks again for everyone's help