alarm going off in middle of night?

[sparkyb]

A woman phoned me the other day saying that her alarm went off in the middle of the night when it was not even set. Any ideas?

 

[roukel01]

If its a wireless one, I've had one that beeps when there is a possibility of RF interference.

OR if the battery is knackered in the panel and there is a slight powercut, that can set them off too

 

[sparkyb]

no its a wired one but battery seems ok.

 

[dim_bulb]

burgulars...

 

[sparkyb]

no its not that either.

 

[philipb]

Get the instalation manual as most alarms have a log that tells you
the last 10 alarms and the zone that caused the alarm.If you havn"t
got the manual you can download it.It could be the tamper circuit
Check that all the covers on the pir"s and the keypads and main box are not
loose.

 

[telectrix]

and the tamper switch/es on the external sounder.

 

[ian]

I would hazard a guess it’s the tamper circuit. The last one of these I had was on the outside bell box.

[FONT=&quot]Ian [/FONT]

 

[alarm man]

tamper fault,could be the bell or a corroded contact,loose lid on a pir,cable fault needs the meter out and take some readings at the panel

 

[sparkyb]

The battery in the bell was only 6.36v. what sort of voltage should the bell battery be? Im guessing at least 12.6v?

 

[telectrix]

count the no. of cells in the bell battery. x 1.2 to get the voltage.

 

[sparkyb]

ok. im away from the job now but is 6.36v likely to be ok then?

 

[telectrix]

seems low. should be nearer to 12v.

 

[sparkyb]

cheers telectrix.

 

[sparkyb]

do you think thats whats causing the alarm to go off then?

 

[telectrix]

difficult to say. the bell battery is there to souynd the bell if the supply to it is interrupted. systems generally will work happily wiythout it. however, if it's duff, it could draw excess current from the panel.

what you have to do is dis. the tamper circiut/s from the panel terminals and meter them for continuity.

 

[sparkyb]

so you think its a tamper fault?
its only wired in 2 pair cable so there is no tamper on the pirs. So you think its the keypad or bell tamper?