Had a customer's panel fail because I skimped on backup battery testing

Last Tuesday I got a frantic call from a dentist office whose alarm died at 2pm. Went out there and found a 7 amp hour battery that was reading 10 volts. I used to just slap in any battery that fit and call it a day. Now I always load test every battery with a specific gravity tester before I leave the job. Has anyone else had a false alarm or system failure traced back to a bad battery?

3 comments

3 Comments

wyatt_fox681mo ago

I had a 12v SLA read 12.4v on a multimeter but it dropped to 8v under a 2 amp load. That panel went off at 3am for a cracked window sensor that never even triggered. The battery was just too weak to hold the system in standby. I dunno man, load testing a battery takes like 30 seconds with a cheap tester. Seems like a no-brainer to me. If you're not doing that you're basically asking for a callback in my book.

noahw531mo agoMost Upvoted

What kind of cheap tester you running for that?

joel28013d ago

Totally agree with you @wyatt_fox68, I learned that lesson the hard way too. Had a 12v SLA showing 12.6v sitting on the bench, looked perfect. Slapped a 3 amp load on it and it tanked to 6v in like 10 seconds. Wasted a whole afternoon troubleshooting a system that was fine, the battery was just a paperweight. Load testers are dirt cheap and save you from exactly those 3am callouts you mentioned. It's wild how many guys skip that step and then wonder why they're chasing ghosts.