On Wed, Sep 27, 2023 at 02:11:03PM -0700, Dick Steffens wrote: > >Intertubes Sez that the Cyberpower 800AVR uses one SP12-7.5 > >SLA battery, which should produce perhaps 13 to 14 volts > >disconnected. That Sealed Lead-Acid battery is probably > >six cells in series, and if one cell has reverse-charged, > >the voltage will be too low and the battery not chargeable. ... > >Replacement SLA are easy to find - Interstate All Battery > >Center has them (some of their stores only have car > >batteries) and Batteries Plus has them. They can test > >the old battery, but they might not honestly tell you > >if it still works (and your 800AVR is borked instead).
> The battery has 12.54v. Sounds like my UPS is borked. Any ideas on > how to test it? And any recommendations on who makes a good, > moderately priced model? At 12.54 volts open circuit, the battery sounds marginal, and may be WAY below spec with a load. I'd take it to an honest battery store for testing. Either the UPS unit or battery could be good or bad ... OR a computer power supply might be slightly wonky; a UPS cannot deliver a huge startup power surge the way a 20 amp wall socket can. An old incandescent light bulb (not LED or fluorescent) makes an "interesting" test load; it draws a startup surge, vaguely similar to the startup surge of a computer power power supply. For my UPS tests, I test multiple 100 watt incandescent bulbs, adding one at a time; a gentler way to learn the limits of the UPS. I use zero incandescent bulbs for lighting, but I keep a box of obsolete filament bulbs for tests like this. Your "800VA" unit produces a maximum of 450 watts. The (sad) reason for touting VA rather than watts is that the voltage and current waveforms can be out of phase with a computer power supply (or electric motor) load. And possibly more wonky than that; A pathological load can overload or damage a UPS, even though the VA and Watts seem small. However ... Before you buy another UPS, purchase a P3 "Kill A Watt" Electricity Usage Monitor, $30 from Amazon, $28 at the Cedar Hills Harbor Freight (NOT Home Despot). That reads watts, VA, power factor, line frequency, even accumulating kilowatt hours. I have more than one P3. I lashed one permanently under my computer bench: two desktop computers, two screens, two KVM switches, and a UPS to "in the darkness bind them". Currently reading 228 watts and 239 VA, more when I run big numeric calculations on multiple cores. Knowledge is power, but so is voltage times current times power factor. Keith L. -- Keith Lofstrom kei...@keithl.com
