ADT Burglar alarm problem


Does anyone know anything about ADT alarms?

This one is not on a maintenance contract.

This PIR sensor is in the lounge and the house is currently empty but it has alarmed 3 times today. Shortly after setting the alarm the alarm goes off and it is always the lounge.

I have wired quite a few alarms and for PIR's I normally use 6 core cable for the
+ - T+ T- and the 2 wires that make up the normally closed circuit, but this one has me stumped.

Normally when you remove any cover from a sensor, the alarm goes into tamper mode, this one does not!

If a sensor was giving false alarms I'd put a wire link in between the two wires for the Normally closed- which would link out that sensor (apart from the tamper circuit) but I did not want to do this on the ADT alarm as at the control panel remote I found a screen that was measuring the voltage of each sensor and also the resistance in Ohms!

I did not want to over ride the resistors that they have placed at the PIR as I thought it might screw the control panel up that is measuring the resistance of that circuit!

I have attached a picture of the PIR circuit board, the wires connected are + -
Then there is a wire in one of the Tamper terminals (the other is empty) and a wire in the C terminal, but there is a resistor between the C terminal and N terminal (which I am assuming is normally closed) and a resistor between the N terminal and the T terminal.

I checked the two resistors with my voltage tester and they were not open circuit but I did not have my multimeter to measure the value of them both. The values of all circuits on the alarm all measured roughly the same value in Ohms according to the control panel.

Can anyone shed any light on this please?

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DIY | Donnas dream house

ADT - all that means to me is ripoff.

unfortunately Chez, it's that long since i dealt with alarm systems i havn't seen ones that monitor in that way.

it looks like a standard Pyronix pir though. without testing the resistor i wouldn't know.

think there are a couple of alarm installer son here arn't there?

Not sure Rich

Alarms are normally very simple, just connect up the 6 wires and you are sorted. Why this one has no wire in the second tamper terminal and two resistors is really beyond me

Hopefully they will get in touch with the installer today

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DIY | Donnas dream house

i understand the resistors used for purpose without using 3-pair cable but not seen a monitoring system so i don't know what the problem could be.

It's an "End of Line" install AKA EOL (dunuo how they came up with that that name)

I know nothing about the ADT installs but I can give you the veritas installation manual that shows how it works. ISTR that most EOL alarms operate on a similar system and they just vary the resistors

I do know someone that was ADL trained and I will pass his details on to you if you PM me, although he has the right to say "the computer says no"

Cheers

Thanks for all the help

They managed to get hold of the original installer and he replaced one of the PIR's

Apparently when they installed the alarm the Lounge was the kitchen, so I was checking the wrong sensor

So when it kept alarming for the lounge it was actually the kitchen sensor that was causing the problem

He also re-programmed the alarm so that the zones are now correct

Thanks again

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DIY | Donnas dream house

lol, no wonder it was a struggle to understand if the pir's were labelled different.