That garage door sensor trick I always rolled my eyes at really works

I've been doing alarms for about 12 years now and always thought the magnet alignment tip was just something old timers said to sound smart. But last month I had a job up in Modesto where a DSC system kept giving false alarms on a garage door contact. After chasing wires for 2 hours I finally tried adjusting the magnet gap down to like a quarter inch and the problem just went away. Has anyone else had a stubborn zone that got fixed by something you thought was nonsense?

2 comments

2 Comments

spencer_ross4h ago

...and honestly I think half the battle with those DSC panels is just trusting the little stuff you normally overlook. Ive had a few jobs where the magnet gap was like half an inch and the contact would work fine for weeks then randomly throw a trouble. Once I shimmed it down to a quarter inch or less it was solid. Another thing I learned the hard way is if the wire run is too long you can get voltage drop on the zone and the magnet alignment stops mattering altogether. For indoor installs I usually keep the gap real tight like 3/16ths of an inch and never have issues. The old timers might not explain it the best but theyve been doing this long enough to know what breaks.

taylor9294h ago

Whoa, hold on, half an inch gap? That is wild to me. I gotta ask, were you using the standard recessed contacts or something like a bigger surface mount one? With the little round ones I always figured anything over a quarter inch was just asking for a false alarm. I've definitely had my share of ghost troubles from magnet gaps that looked fine but were just barely too far.