Need help with Smart-UPS 1250 fuse

[Maxxarcade]

I am replacing the batteries in a Smart-UPS 1250 that has been sitting for years. The last one I did had a different style fuse that was smaller, but the other ones I have use this odd circuit board with two 50 amp fuses.

I can't get it to fit no matter what I do. There is no clearance above or in front of the batteries. Am I missing some angle brackets or something? Anyone have pics of one of these assembled? It's driving me crazy, I tested it with a temporary jumper and everything works fine, but I can't put it together without the fuse in place

[Maxxarcade]

Re: Need help with Smart-UPS 1250 fuse

Got it to work by stacking two sets of the black spacers and using longer screws, And mounting it in front of the batteries with the fuses closest to the bottom. It barely fit, so I put a protective sheet of plastic over it in case the front panel circuit board may end up touching it.

When I first tested it out, it went to low battery mode right away. I let it charge till the fan stopped, and it ran a 500W load in low battery alarm for over 20 minutes before it actually shut off. Hopefully it will recalibrate itself and work properly after the next charge.

The batteries are cheap ones from China (Universal Battery) but still seem to pack a punch. Let's see if they outlast the ones from Vietnam that are in all my other UPS units

The best part is that the seller sent me the wrong pair of batteries at first, but told me to keep them and then sent the proper ones. Then I found someone on Ebay who sold me a pair of Back-UPS 600's for $35 shipped, and I put the new batteries in them. So I ended up with a Smart-UPS 1250 and a pair of Back-UPS 600's with new batteries for less than $100 total

I still have 3 more Smart-UPS 1250's left in the pile, which will get new batteries when I can afford it. I picked all but one of my UPS's out of the trash, and they are running great with new batteries now I love good free stuff.

[japlytic]

Re: Need help with Smart-UPS 1250 fuse

For UPS units with batteries in series: be sure to charge the batteries evenly - each battery must have a voltage range of 0.1V after a 6 hour rest after being fully charged with the charger disconnected (e.g. battery A is 12.82V and battery B is 12.78V, which gives a range of 0.04V)
Also, have you got a picture of the fuse board successfully fitted with longer screws?

[Maxxarcade]

Re: Need help with Smart-UPS 1250 fuse

Regretfully, I don't have an assembled pic. I was too pressed to get it together and installed in the server rack.

Hopefully the batteries will be ok, since they were bought as a kit. I had read somewhere that the batteries will be evenly charged after doing two complete charge/discharge cycles with the UPS, which also calibrated the battery meter.

I'm a bit worried about the quality of the batteries though, since I had a small UPS with a single 12v 7ah battery by the same company, and it lasted less than two years. Maybe the more advanced charging circuits in the Smart-UPS, and the fact that these batteries are bigger, will make these last longer.

[kc8adu]

Re: Need help with Smart-UPS 1250 fuse

those small ups units are very hard on that tiny 7ah battery.
i have seen 50+amp discharge rates on an apc back ups 650
any degradation at all and they drop below the low voltage shutoff as soon as the inverter turns on with a load.cheap crap batteries are even worse.
btw those universal brand batts dont hold up in wheelchairs very long.
those vietnam batts from gruber dont either.
if you have a mk or east penn/deka dealer nearby spend a few more $.