Door contact - trouble shooting

[Jupiter01]

I have one of these on a shed door:

It's wired in with two wires (red and black) and set as Normally Closed. This works fine on my Texecom premier elite system.

I wanted to add another door contact as a new zone. I used two spare wires (blue and white) from the existing cable to connect to this new door contact. I then wired this into a new zone and configured on the keypad to match the existing door contact. This new door contact does not work. When I view the Zone Status, it reports "Active 65k" whether the door is open or closed.

I then did the following by way of trouble shooting:
- I removed the blue wire from COM and added a small wire between COM and Zone 15 (where the white wire is connected). This changes to the Zone Satus to "Secure". I think this proves that the zone on the panel is working correctly.
- I then checked continuity along the blue and white wires using my two pole tester and we have continuity.
- I re-did the connections on both ends. No difference
- I then swapped the two door contacts (just the bit with the cable and the one that wasn't working, also doesn't work with the previously working zone and vice-a-versa. When I swapped these, I am still using the same coloured (as was the case originally) wires on both ends i.e. the "defective" contact is using red and black wires connected to blue and white on the cable that runs up to the panel.

This appears to suggest that I have a faulty door contact but thought that is rare as there isn't much to these contacts...

I would appreciate your advice with this. Thanks in advance.

 

[sparkymarka]

Faulty or ….has it got resistors built in ? Have you got the package it came in or is there a sticker on the contact ?

 

[Jupiter01]

UPDATE - I used the red and black wire on the device and hey presto! All working.
I was previously using the blue and white wire on this. I assume that the black and red must be used and you can’t pick any other colour.

All my earlier tests missed this…

 

[sparkymarka]

? … are you saying you just picked two random wires off the contact and expected it to work …you didn’t check which pair was the alarm pair and which was the tamper loop ?

 

[Jupiter01]

? … are you saying you just picked two random wires off the contact and expected it to work …you didn’t check which pair was the alarm pair and which was the tamper loop ?

Embarrassingly, I did.
It was some consolation to have thought about this later and fixed it…