Veritas 8C (old model) goes off randomly

[jaysta]

I have been having a nightmare with my house alarm these past few months.

Randomly through the day or night the alarm will activate with either zone 3, 6 or 24 Hrs showing when I go to reset the alarm. This happens when the alarm is armed or disarmed.

So far I have:

Walk test and discovered that door and vibration sensors, PIRs and PAs are on their own zone, everything seemed ok
Replaced the battery, no joy
Looped zones 3 and 6

The alarm still goes off randomly but only shows 24 Hrs as the culprit. I don't have a clue what 24 Hrs however something tells me it's either to do with the bell box or tamper.

Please can someone help me diagnose what has gone wrong in our alarm?

 

[Handymanjo]

24 hr could be the bell box tamper , the global tamper or the panel lid.
This will be a process of a limitation ?
Link out bell tamper O volts to t - tamper return with a link.leave for a few days if problem goes away then bell box problem ?
If you still have a problem ńow link out tamper on panel with a link,leave a few days .if problem goes away it is a problem with the global tamper which will lid on a pir or shock sensor ?
If problem still there could be control panel lid ?

When you think you sorted you can then remove the links you have fitted.
These tamper faults can be easy to sort or a pain in the ***

 

[sparkymarka]

What devices where on zone 3 and 6 sounds like it's dropping power to activate 3,6 and tamper ( bell ? )
How old is the bell box ? Make / model or picture , could be water damage to the bell , seen it drag the power down before.

 

[secureiam]

Old as in 00 to get into the menus or old as still uses fuses?

Just if its prog to get into the menus then you can use the engineers code and the event log to indicate where the tamper is coming from or the walk test.
Unfortunately the auxiliary tamper and the bell tamper share the same number, but the other tampers like the lid have a dfferent number to represent the fault.

if its the powered devices giving you grief as already said, then it limits where you need to look, would also ask where do the cables run.

 

[jaysta]

Thanks for all the replies.

24 hr could be the bell box tamper , the global tamper or the panel lid.
This will be a process of a limitation ?
Link out bell tamper O volts to t - tamper return with a link.leave for a few days if problem goes away then bell box problem ?
If you still have a problem ńow link out tamper on panel with a link,leave a few days .if problem goes away it is a problem with the global tamper which will lid on a pir or shock sensor ?
If problem still there could be control panel lid ?

When you think you sorted you can then remove the links you have fitted.
These tamper faults can be easy to sort or a pain in the ***

Cheers HMJ, I'll keep this in mind when I get chance to take another good look at it.

What devices where on zone 3 and 6 sounds like it's dropping power to activate 3,6 and tamper ( bell ? )
How old is the bell box ? Make / model or picture , could be water damage to the bell , seen it drag the power down before.

Z3 is a PIR as is Z6. The bell box has been there since before I bought this house in Sep 2007. I'll try and get a picture of it.

Old as in 00 to get into the menus or old as still uses fuses?

Just if its prog to get into the menus then you can use the engineers code and the event log to indicate where the tamper is coming from or the walk test.
Unfortunately the auxiliary tamper and the bell tamper share the same number, but the other tampers like the lid have a dfferent number to represent the fault.

if its the powered devices giving you grief as already said, then it limits where you need to look, would also ask where do the cables run.

Old as in I think I may have seen Texecom 1996 printed on the PCB. The cables to the bell box and PIR for Z3 and Z6 are run under the floorboards.

I was away for a couple of days and came back to no issues on the alarm. However, on the night we came back the alarm was going off again and again and carried on with its randomness during yesterday. This led me to think that maybe the PSU can't cope as while we're in the PIRs are detecting and causing a little more power draw than when no one's in.

I yanked the fuse out of the FCU and all was well while on battery for a good 12 hours. Then when the battery ran out early this morning I pushed the fuse back in and so it's been ok. I'm pretty sure it'll catch us by surprise before the day is out so I will try your suggestions.

 

[sparkymarka]

Ok , so there are no more powered devices on the alarm ? Pirs/shock sensors ?

 

[jaysta]

Ok , so there are no more powered devices on the alarm ? Pirs/shock sensors ?

Yes, there's the following:

Z1 door sensor
Z2 PIR
Z3 PIR
Z4 shock sensor
Z5 door sensor
Z6 PIR
Z7 PA
Z8 PA

And the bell box outside

I don't think the door sensors and PAs use much power though do they?

 

[sparkymarka]

They don't use any , would you say the devices that where on zone 3 and 6 where further away from the control panel , than 2 and 4 ? Do you have a multimeter ?

 

[jaysta]

They don't use any , would you say the devices that where on zone 3 and 6 where further away from the control panel , than 2 and 4 ? Do you have a multimeter ?

I do have a multimeter yeah.

From the control panel Z3 is the furthest away, followed by Z4, then Z6 and then Z2.

I'm intrigued as to what are you thinking next?

 

[sparkymarka]

Type of device and distance can be affected by voltage drop, you need to take DC voltage readings in the panel for a start , battery , aux supply and bell ( 12+ A and D 0v )

 

[secureiam]

So your only getting false alarms on the two zones that go under the floorboards, and only when your in the house?

 

[jaysta]

So your only getting false alarms on the two zones that go under the floorboards, and only when your in the house?

No, we're getting false alarms on Z3, Z6 24 Hr whether the alarm is armed or disarmed.

 

[Handymanjo]

Does the bell box ring when the alarm is unset when this fault occurs?
If bell box rings then could be tamper fault on bell box causing 24 hr fault on panel.

You may need to start linking things out to find fault.
See you have a multimeter take resistance reading of aux tamper circuit to see if high could point you to lids on sensors? If not bell box

 

[jaysta]

Does the bell box ring when the alarm is unset when this fault occurs?
If bell box rings then could be tamper fault on bell box causing 24 hr fault on panel.

You may need to start linking things out to find fault.
See you have a multimeter take resistance reading of aux tamper circuit to see if high could point you to lids on sensors? If not bell box

I'm sorry I didn't mention this initially. The answer is no, when the alarm activates when the alarm hasn't been armed the bell box doesn't ring... only the internal sounder rings.

 

[Handymanjo]

When was the last time you triggered the alarm to see if the outside bell box was working correctly ?
Could be faulty bell box not sounding ? and has an issue causing tamper fault