Pro tip: Learned the hard way about resistor values on zone inputs

I've been installing DSC panels for like 8 years and always just used the default 1k resistors on every zone. Last month I had this house where a door sensor kept showing as tampered during the test, turns out the panel was expecting 2.2k for that zone according to the programming sheet. Has anyone else run into a panel where the default resistor values aren't what you'd expect?

2 comments

2 Comments

patricialee29d ago

Oh man, that brings back memories. I had a similar situation with a different brand where the resistor values changed based on whether you were using NC or NO sensors. It's funny how we get into these habits, like always using the same screwdriver or sticking with the same brand of wire nuts. In my experience, a lot of these little gotchas boil down to the fact that manufacturers update their hardware but don't always make the changes obvious on the box. It's kind of like how you'd expect a light switch to work the same way in every house, but then you run into a three-way setup or a dimmer that throws you off. So yeah, always double check that programming sheet even if you think you know the brand.

felixfisher28d ago

Did you find that the software version mattered more than the hardware revision, or was it strictly a resistor issue?