For several years—actually more than several years—I used an APC BackUPS 600 uninterruptible power supply (UPS) in my home office to keep my electronics up and running in case of a power failure. It saved my bacon several times when the power went out here.
There was always one situation that kind of griped me, however. I have a Brother MFC-7360N laser printer/scanner, and whenever I would print a document, the UPS would kick on as if the power had dipped. I emailed Brother about this and they informed me that this is exactly what was probably happening, as they designed the printer to draw so that it would draw a large amount of current so that it would heat up faster. While this was annoying, it wasn’t that big a deal, as I don’t print documents very often anymore.
This spring, however, the situation worsened. Whenever I went to print something, the UPS either didn’t kick in fast enough, or couldn’t supply enough power, and my computer would actually turn itself off. Not good. I surmised that the battery in the UPS was just not holding a charge like it used to. Since I really needed the UPS to supply more power anyway, I decided to purchase a new UPS instead of just replacing the battery.
What I bought was a Liebert PSA5 1500VA. This unit has more than twice the capacity of the APC UPS (the 600 stands for 600 VA capacity) and did work better than the APC. I didn’t experience any weird stuff when the printer started up. “Great!” I thought.
Then, about six weeks ago, the Liebert UPS just turned itself off. “EC01” it said on the LCD display. I looked that up in the manual, and it said EC01 indicated a shorted output. I crawled under the desk, disconnected all of the devices plugged into it, and turned it back on. It beeped and displayed EC01 again. “Damn,” I thought.
I couldn’t just not work, so I went downstairs to find some power strips. As I was searching for something I could use, it occurred to me that I still had the APC UPS somewhere. The battery was weak, but it would still provide some protection. So, I brought that upstairs along with a six socket power strip.
I plugged my Mac, the cable router, and my wife’s laptop into three of the four battery-backed outlets, then turned on the UPS. Nothing. Shoot, I thought, the battery must be so gone now that it won’t even turn on. So, I plugged everything into the power strip and the four surge-protected outlets on the APC UPS and got back to work.
The next morning, I called Liebert’s 800 number. I explained the problem, and after a couple of questions, they said that they’d send me a new unit as quickly as possible. At least that went well. I waited almost two weeks to get it, but it’s been working fine ever since I installed it.
After I unplugged everything from the APC UPS and power strip, I hauled them back downstairs. As I was carrying them, it occurred to me that the APC UPS felt a little light. Then, I remembered that I had taken out the battery to measure it so that I could buy a new one. No wonder the battery-backed outlets didn’t work. There was no battery!
I ordered a new battery from Amazon, which arrived in a couple of days, installed it, and the APC UPS is as good as new. I’m now using it in the shack ahead of the 13.8 VDC power supply and the shack computer.
I still have the defective PSA-5, too. Liebert didn’t seem to want it back, so it’s just sitting in a box, under the desk. I may crack it open and see if there’s anything obvious that’s causing the shorted output.
UPDATE 10/31/22: The APC UPS passed its first test just now, at least the first one that I’m aware of. The power went out here for a couple of seconds while I was in the middle of a QSO, and the UPS just powered right through it.