I always thought my APC stuff was quite reliable but having read this thread it has reminded me of a couple of issues I have encountered with them.

One UPS I got cheap because it wasn't working properly. Plugging a lamp into it and switching it over to battery made some arcing sounds and the light would dim for a second or so. Opening it up revealed a faulty relay, which once replaced fixed the problem. I probably can't blame APC for that one though, it didn't look like they were using cheap parts.

The other problem I've noticed relates to things they didn't really test very thoroughly as it's a situation they didn't expect would happen. When the batteries reach the end of their life, they expect you to replace them within a couple of days. However if you take too long, when the time comes around for the unit to do a self test it will switch to battery, then realise there's no power for the inverter, so switch back to the mains. But that double-switchover time leaves the load without power for just long enough that all the PCs reboot.

I must admit that it is kind of annoying having a device that's supposed to protect your network cause more outages than it prevents!

I'm curious how other brands behave in this respect. If you disconnect the battery from an Eaton unit and tell it to test the inverter, does it cut power to the load for long enough to reboot a PC, or see a lamp quickly switch off then back on again?

I think I experience this problem more than most because where I live the temperature is around 30-35C (86-95F) for six months of the year. Not living in an air-conditioned data centre, the UPS seems to end up cooking the batteries after a couple of years. I've considered trying to modify them to leave the fan running all the time as my 1400XL only switches it on when it gets really hot (maybe 40C/104F) and the SU3000 never turns it on unless the inverter is running, but I'm not sure how much difference it would make. I think I'd get a better result using bigger batteries and locating them outside of the UPS.

Well I got a eaton unit I was talking about the other day. Well it was shipped FedEx. Yep it's a goner. 🙁 . But the case is mostly ok '. So not all is lost! Time to go diy? No mega big reserve bank? I don't know what I'll do with it yet. It all depends on if I can get another one or not. I bet I could put close to 20 battery's in its case. The transformer was the size of a football. And the entire unit was 90 pounds. 😵

Jade Falcon wrote:

Well I got a eaton unit I was talking about the other day. Well it was shipped FedEx. Yep it's a goner. :( . But the case is mostly ok '. So not all is lost! Time to go diy? No mega big reserve bank? I don't know what I'll do with it yet. It all depends on if I can get another one or not. I bet I could put close to 20 battery's in its case. The transformer was the size of a football. And the entire unit was 90 pounds. :dead:

Any idea what about it is broken or have you mostly just verified that it doesn't turn on so far?

You can potentially go DIY, or you could get a newer UPS with a more modern circuit design, and possibly stuff it in the old case for the vintage look.

DIY UPS is not the easiest thing in the world to make but it's certainly possible and is also not the hardest thing to DIY, either.

It went poof when I powdered it on. It has bad mosfets (some cracked others brunt) and damage to the PCB. And the transform looked like it's seen better days.

I may put a newer UPS inside it or use it as a second ebm. I can make a diy one, but I don't know we're to begin in making one that's able to switch over to the battery's when the power is cut and tell the pc how much battery life is left. So I'll probably ether use is for a ebm or stuff a newer ups it in.

Ill probably get a newer smaller unit to stuff inside it and have it power my monitor.

Most people DIY them with a DC-AC inverter. Make sure to get a "pure sine" inverter, and make sure the datasheet doesn't forbid use of power supplies with PFC (power factor correction). If you charge them with the right charger with enough capacity you can make an online UPS. Or use a small engine and an alternator from a car and you've got an inverter generator. For a line interactive one you could get some high quality relays (or even higher quality and capacity - "contactors" - used in HVAC and in general with more powerful circuits than relays) and hook them up to some sort of line voltage detection, but it could be tricky to balance a quick response time (so your stuff doesn't turn off before it switches to battery) and proper debouncing (so it doesn't oscillate between mains and battery, which would kill the UPS and/or trip your circuit breaker and/or kill some of your load).