Yes, I think you're right. I wouldn't normally work on an electronics board that's got power.
Someone told me that my Securit 800L loses the programming settings if I remove power. I don't think this is the case. Does anyone know for sure?
I have an existing Securit 800L system. I want to add a second door to the final exit circuit, and also an extra PIR. If possible I want to do this without the SAB going off and annoying the neighbours. I definitely can't access the bell at the moment because there's building work going on...