Question about a weird voltage reading on a 12 volt panel

I was finishing a job in a new build in Springfield last Tuesday, checking the final connections on a Vista 20p. My meter showed 13.8 volts at the main panel, which is fine, but at the keypad in the master bedroom, I was getting a steady 11.2. That's a bigger drop than I've ever seen over a 50 foot run of 22/4. I traced the whole line and found a staple driven right through the jacket and into the red conductor. Has anyone else seen a voltage drop that specific from a single staple short? I'm starting to think I should be checking voltage at every device, not just the transformer.

3 comments

3 Comments

shaneb1620d ago

Had a staple do that once, but it was on a longer run for a garage door sensor. Voltage was all over the place until I found it. Checking at the device is a good habit now.

king.andrew20d ago

Wasn't that from the staple's insulation damage?

tessa_clark7420d ago

Wait, a staple did that? I've seen some chewed up wires from mice, but a staple causing voltage swings is wild. It's crazy how something that small can mess up a whole circuit.