Strange false alarm.

[squowse]

Came back to find the alarm had triggered yesterday.
Strange thing is looking at it the time between the triggers was exactly 2 hours and 14 minutes both times. As if there is some kind of fault that was ignored for a set period of time? The sensor has not triggered a false alarm before. There was no evidence of an intruder.

I am also not 100% clear what "Guard Restore" and "Locked Out" mean exactly.

This is the log

0015 09:43:01 26/04/2013 Alarm A . Zone 004 Guard Alarm - Shed
0016 09:43:32 26/04/2013 Restore A . Zone 004 Guard Restore - Shed
0017 11:57:06 26/04/2013 Alarm A . Zone 004 Guard Alarm - Shed
0018 11:57:08 26/04/2013 Restore A . Zone 004 Guard Restore - Shed
0019 14:11:14 26/04/2013 Alarm A . Zone 004 Guard Alarm - Shed
0020 14:11:14 26/04/2013 Alarm A . Zone 004 - Shed Locked Out
0021 14:11:17 26/04/2013 Restore A . Zone 004 Guard Restore - Shed

 

[sparkymarka]

guard alarm means zone is open, restore means it has gone closed again and lockout means it has been disabled as the panel is probably set to 3 rearms. what detector do you have in the shed ?

 

[squowse]

can't remember the brand and model but it is dual tech.
how does the sensor get re-enabled - when the alarm is reset?

strange pattern of guard alarms though isn't it?

 

[sparkymarka]

yes its back to normal when you reset alarm... once had a premier 24 that had a false alarm most days at 13.01 ended up putting a mains filter on system, even went to site at that time set system and guess what ? it didnt happen lol

 

[scott1980]

I wouldn't read anything into the fact that it went off at those particular times. We had an issue on a system once where a double door with two sets of contacts on it false alarmed at the same time for three days. Replaced the contacts, false alarms stopped.

I would cover the detector over with a piece of card and place the detector on soak test for a week or so. That should tell you if it's the detector or something environmental triggering the detector (providing all the other checks like cable readings/connections/voltages are OK)

 

[EightyTwo]

I agree with scott1980 but wouldn't use the card - masking the detector AND putting it on soak test will only check the wiring and panel.

I'd be inclined to check for spiders (in a shed), or any other creatures, and make sure that the microwave sensitivity/range isn't set too high - it shouldn't see things outside the shed!! Put it on soak test and see what happens.

I bought some spray stuff from a cheapy shop called "No more spiders". It's chestnut and clove oil and it seems to work really well. In a house, I spray it on a paper towel or kitchen roll and shove it up the back of the detector. In a shed, I'd let it soak into the wood... Works great for cameras, too

 

[Boilerman2]

In my experience even Dualtechs can be problematic in a shed they suffer from extremes of heat and are far from draught proof meaning that both Technologies could trip simulatainiously