Sensor query

[Guest spbaldock]

I need to change a sensor on our alarm system and replace it with one that doesn't detect animals. However, when I open the existing one, the tamper alarm goes off. I can deactivate it from the control panel, but in terms of undoing the wires, how do I do this without electrocuting myself (albeit 12vDC!)?

Since the battery will be supplying the power if I disconnect the whole alarm from the mains, should I disconnect that as well (and set the alarm off) or does it really not matter, and just wire it in anyway?

Thanks

[Brian c]

Disconnect the wires, one by one, snipping the bare ends off as you do so.

Replace the detector and reterminate the cables one by one. Close everything up and enter your code and/or press reset (depending on your alarm) and all should be well. Remember to test the sensor works!

If you are in any doubt or have any concerns, leave it alone and call a professional.

[Guest spbaldock]

Thanks - so, not to worry about the power supply then?

[Brian c]

Yes.

Make sure none of the wires touch each other or you will blow a fuse.

So long as the system is installed as it should be, you won't get a shock from the 12V supply on the cable.

[Guest spbaldock]

Thanks again. One final question, if I were to replace the PIR with a door contact, if I use a connector block, how do I wire the tamper cables (since they aren't needed for the door contact)?

[Guest]

Thanks again. One final question, if I were to replace the PIR with a door contact, if I use a connector block, how do I wire the tamper cables (since they aren't needed for the door contact)?

35364[/snapback]

They are actually. The tamper pair is to protect the cable as well as the device so you should extend the tamper wiring to the contact and connect them together on a spare terminal.

(Knew I'd seen a picture somewhere, courtesy of Mr Partridge himself).

Picture of door contact wiring.

Also, when you say connector block I think you mean tamper protected junction box don't you?