Uploaded June 2018 | Updated September 2026, 2 weeks ago
At random times over the past several months, an APC Back-UPS NS1080 has been throwing a "relay welding" fault code. In this video, I try and fail to provoke it into doing the same while I'm actually watching.
I am pleased to report that this time around, the Smart-UPS 420 didn't whistle like a teakettle when its battery failed. It actually failed a self test, and turned on the "bad battery" indicator LED. That's a pretty rare occurrence for a Smart UPS. (I knew something was up, because prior to the failed self test, it dropped the attached load during a power outage.) Its battery failed shorted and was VERY hot (about 120°F/49°C) when I removed it.
I have another NS1080 that I believe to work, and I may put the batteries from this one into it. I may also try a MUCH heavier load.
It's never the flea market, hamfest or thrift store "junkers" that fail. Of course it's the one I bought new.
At random times over the past several months, an APC Back-UPS NS1080 has been throwing a "relay welding" fault code. In this video, I try and fail to provoke it into doing the same while I'm actually watching.
I am pleased to report that this time around, the Smart-UPS 420 didn't whistle like a teakettle when its battery failed. It actually failed a self test, and turned on the "bad battery" indicator LED. That's a pretty rare occurrence for a Smart UPS. (I knew something was up, because prior to the failed self test, it dropped the attached load during a power outage.) Its battery failed shorted and was VERY hot (about 120°F/49°C) when I removed it.
I have another NS1080 that I believe to work, and I may put the batteries from this one into it. I may also try a MUCH heavier load.
It's never the flea market, hamfest or thrift store "junkers" that fail. Of course it's the one I bought new.
