Fault on Scantronic alarm/PIR

[HERTS P&D]

Hi, I have a fault with a PIR, making the alarm go off. But not every time. So the first thing I done was to fit a new PIR but the fault is still there but intermittent.

Is the next step to rewire from the control box to the PIR, or is there anything else that it could be.

I have also just fitted a new battery.

Andy

 

[secureiam]

how olds the system?

you have replaced the back up battery.

you have an intermittent fault on the new pir as well as the old one, other pir's okay?

do you have any spare cores for the wiring the pir, before you go looking at running new cable?

 

[HERTS P&D]

The system is approx. 25 years old. I have replaced the battery in the control box as it was 5 years old anyway. The intermittent fault is now on the new PIR, all the rest are OK and no spare cores for wiring the PIR.

That's why I'm thinking running a new wire is the only option?

Many thanks for any advice

Andy

 

[sparkymarka]

What scanronic panel is it ?

 

[HERTS P&D]

9800

 

[sparkymarka]

So it's got separate tamper pair ( with a bit of luck) try swopping the alarm and tamper pair around to prove its the cable check for bad connections in panel including power pair ..

 

[HERTS P&D]

It has the following wires:

Tamper with a white wire and a black wire
Alarm with a yellow wire and a red wire
Power with a blue wire and a green wire.

Hope that makes sense.

Andy

 

[secureiam]

good call mark

if you swap the tamper and alarm wires round both ends.

 

[sparkymarka]

Use the tamper pair to prove point , swop at panel and link out tamper, do check the panel connections as I've had panels which have been fine for years only to check at panel end and its pulled out of the connector !

 

[HERTS P&D]

OK, I'll do that in the morning and report back.

What should or shouldn't happen??

Andy

 

[sparkymarka]

If your still getting alarms after this it could be a fault on the power pair dropping out power to the PIR , what detector did you fit and where is it ? What area eg kitchen, garage ?

 

[secureiam]

Given both detectors do it old and new its unlikely to be the pir.

but that leaves you with interference cable damage and the panel its self

I have known panels give false alarms because of dry joints in the panel.

You could leave the tamper unlinked, and because you swapped the wires round, if it was the alarm pair that were bad, you should now get a tamper rather than a zone active.

How often is it going off?

 

[EightyTwo]

I think that it is unlikely to be the cable - but swap the pairs anyway. It's easy to do and will prove a point.

Have you taken down your Christmas decorations yet? There's nothing like a big foil star hung over a radiator for generating false alarms - except maybe a set of angel chimes! i went to one office where the girls had decked out someone's desk for his 40th, including a helium filled foil baloon under the air conditioner...

If it's not the PIR or cable, it can only be the panel or the environment. To eliminate the former, swap the wiring with another zone (say, dining room for living room) and see which circuit alarms (check circuit type - Er, A, FE, etc.). If it's the same circuit, the problem is with the panel. If it's the other circuit, the problem is with the cable/PIR/environment.