Optima XM panel to Veritas V8

5 Oct 2022
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United Kingdom
Hi All

Hoping someone can help me help a neighbors son, who decided to swap out their parents old alarm and got stuck.

I’ve managed to do a drawing of what I’ve worked out, but there’s one connection point that we can’t find (guessing under floorboards or carpet). I’ve traced all circuits physically except for the dining room PIR which I did continuity tests and found where some of them come and go to and it’s all marked up on the attached picture.

All the circuits on the left of the drawing are OK, I’ve just not shown the red/black connected to 12v.

The old alarm panel was an Optima XM and had a PIR in the dinning room, that works with just 1 wire to zone 3 and somehow worked via the bell box tamper to 0v – but I’m not familiar with this type of wiring (have only done my own Texecom Premier Elite install).

I know yellow is hard to see, so just to confirm the yellow going to the bell box is connected in the loft to both green and black to the landing PIR.

So, the questions are please:

How might the bell box have been wired? He’s not got a photo prior to disconnection, but says there was more than 1 wire in at least 1 of the terminals. I’m thinking if I can understand the old wiring, I might get the whole system running on the new Texecom Veritas – if it can do the 1 wire to a zone thing?

How might the dining room remaining wires be connected, as the only faults standing are zones 3 and 5?

I’m not at a complete loss as it is, as I know I can just wire the Veritas panel to the external sounder as standard S D C B A, loop out the dining room PIR, and tweak the wiring to the landing PIR so everything else will work, apart from the dining room.

Cheers all


  • alarm overview.jpg
    alarm overview.jpg
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That’s a mess …. I would have either ripped it out and re wired or fitted a wireless alarm …..
any way the only way I can see how it was done with a single wire return is …..at the pir link the 12v + to one side of the alarm relay and use the single wire as a return to the panel , you will have to check at the panel to see which side of the zone provides 12v ….put multimeter on 0v and the other probe on the zone inputs , one of these two terminal should give you 12v , put the single return wire on the other terminal …

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