Europlex panel - false alarm

[bonzer]

Last night one of our PIRs triggered an alarm. Now, I know spiders and bugs can cause false alarms but when I looked at the log on the panel it reported that the zone was 'closed 1050'. To seems to indicate that the zone wasn't triggered and was within the correct loop resistance window of 1000 ohms. So why would it have triggered in a closed state?

 

[SLIPSHOD & SLAPDASH]

I dont know that panel, but does that mean the time the zone closed ?

 

[binky]

'close the loop' as in triggered. Alarms are a series of open switches (apart form the tamper loop) so when they trigger the close the loop to set-off the alarm. At least that's how I would read that message.

 

[Richard-the-Ninth]

I would have to ask, what else does the log say?

What does it show prior to what you have typed?

What does it say after what you have typed?

Have you looked in and behind the offending pir?

 

[SLIPSHOD & SLAPDASH]

'close the loop' as in triggered. Alarms are a series of open switches (apart form the tamper loop) so when they trigger the close the loop to set-off the alarm. At least that's how I would read that message.

You have that the wrong way round, all alarms i know of are normally closed inc the tamper.

 

[binky]

ok, I stand corrected  :innocent

 

[Richard-the-Ninth]

It depends which alarm you refer to:

Fire alarms are open circuit going closed*

Intruder alarms are closed circuit going open *

*Non addressable fire alarms

*Some parts such as pressure mats and exit terminate buttons are open going closed.

 

[SLIPSHOD & SLAPDASH]

Not all fire alarms are open circuit  inc any addressable .

 

[bonzer]

What does it show prior to what you have typed?

It shows the time that the alarm (night mode) was set

What does it say after what you have typed?

It says '***ALARM***' and the same time as the message in the OP.

Have you looked in and behind the offending pir?

Not yet. I was trying to understand why it would register an alarm for a non-alarm condition. With the Europlex panel, a 'closed' circuit is a non-triggered circuit. It goes 'open' (@2000 ohms) when triggered.

 

[Richard-the-Ninth]

What does the log say if you set your alarm, move in front of the same sensor then turn it off ?

I am guessing that that particular device activated (open) then it cleared (closed) so the panel is showing the last state of the detector.