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Would anyone share UPS recommendations? My old one has apparently died. I've had two power flickers in the past week, and both times the attached PC didn't even have time to shut down before the UPS gave out (corrupted the WUs too ). I need something that will handle about 500 watts and last long enough to allow the PC to shut down.
I currently have a Cyberpower 1350PFCLCD.

cheapest one is this one: https://www.amazon.com/gp/product/B000FBK3QK
After about 6 months, it still works on an 800W PC (for about 1 minute).
The 1500 isn't Watts, and is grossly overrated.

I'm currently using a few APC br1500g units, they seem ok but they rarely need to do anything around here.

How old is the UPS? More than 3-5 years, then it is probably just that the batteries have died. They are just standard SLA batteries, about $30-35 each depending on where purchased. Many suppliers, and cheaper than purchasing through Cyberpower. In addition, in the same size battery case, you can often get a higher capacity battery than originally supplied with the UPS.

After about 6 months, it still works on an 800W PC (for about 1 minute).
The 1500 isn't Watts, and is grossly overrated.

800 W is at or above the rated output for most 1500 VA rated UPS, usually you want to be under 60% of capacity. That application calls for one rated around 2000 VA or better. They explicitly state 900 W for this item.

Joe_H wrote:How old is the UPS? More than 3-5 years, then it is probably just that the batteries have died. They are just standard SLA batteries, about $30-35 each depending on where purchased. Many suppliers, and cheaper than purchasing through Cyberpower. In addition, in the same size battery case, you can often get a higher capacity battery than originally supplied with the UPS.

After about 6 months, it still works on an 800W PC (for about 1 minute).
The 1500 isn't Watts, and is grossly overrated.

800 W is at or above the rated output for most 1500 VA rated UPS, usually you want to be under 60% of capacity. That application calls for one rated around 2000 VA or better. They explicitly state 900 W for this item.

I'm in the process of checking the batteries, but so far it's giving no indication that the batteries are faulty. The unit is about 3 years old though, so it's possible. The LCD is showing 53% load right now, and a 7 minute runtime at that load. In practice, it has a zero runtime. Could still be a faulty battery though.

This unit has 2 batteries in series, the replacement battery kit is around $70 from various sources.

Yep, batteries bad.
Called Cyberpower support and tech said that the minutes remaining is solely based on battery voltage.
Found replacement set for $40 .

If they are agm batteries then using a smart charger like a ctek might give them a new lease of life? .. new batteries are cheaper than the charger but if you know someone who has one that will work on the batteries in question it might be worth a try?

Neil-B wrote:If they are agm batteries then using a smart charger like a ctek might give them a new lease of life? .. new batteries are cheaper than the charger but if you know someone who has one that will work on the batteries in question it might be worth a try?

Maybe, but usually once these cheap agm batteries are dead, they are beyond repair.
Also, I gave the CP tech the serial number on my UPS, and it's quite a bit older than I thought. I've only owned it for a few years, but apparently it sat on a shelf for a few before that, so those batteries are quite old.

Also making sure the bios is to to always on so it comes on when the power is back up.

chabgood wrote:Also making sure the bios is to to always on so it comes on when the power is back up.

Yep, all mine are set up that way.

I'm thinking of swapping out the lead acid batteries, with Li Ion batteries of similar dimensions.
They should offer longer run times, and more recharge cycles. Also last longer.

You would need to find an UPS that is based on LiIon batteries, you can't just substitute as the charging circuitry is not compatible between the two.

Good deep discharge lead acid batteries will last longer than LiIon in recharge cycles.

Newer PSUs with Active Power Factor Correction (PFC) may not do well with cheap UPSes and synthetic sine wave forms. Spend the extra $$ for a true sine wave UPS, like Cyberpower's CP1500PFCLCD.

jrweiss wrote:Newer PSUs with Active Power Factor Correction (PFC) may not do well with cheap UPSes and synthetic sine wave forms. Spend the extra $$ for a true sine wave UPS, like Cyberpower's CP1500PFCLCD.

I agree 100% with spending the money to get a true sine wave for many reasons. It's the only kind of inverter I buy anymore.

Joe_H wrote:You would need to find an UPS that is based on LiIon batteries, you can't just substitute as the charging circuitry is not compatible between the two.

Good deep discharge lead acid batteries will last longer than LiIon in recharge cycles.

You can. the charge/de-charge voltages of both are near identical.
plenty of car/motorcycle batteries that got hot-swapped with lithium batteries. Charge voltage of Li Ion =14.4V, that of Lead acid is 14.1V.
So there's no danger of over charging.

Lithium can sustain heavy loads better for longer. But once it drops far below 2,7V, it's output amperage is pretty much pudding.
10.8V,and the UPS would probably shut off, like it does with a lead acid battery.
While officially 2,8V is the cutoff voltage for cells, many people have gone much further (2,65V, and 2,5V even) and suffered no ill consequences trying to charge up the cells.

The added benefit of Li battery packs, is higher supported wattages. The readout (meter) will just stay on full (90+%) most of the time, until the battery is about to die. Then rapidly fall off, so the countdown timer might be off. But it works just fine.
The only thing is, with an 800/900W UPS, swapping to Li, I would be able to pull a 1000+W load. Once the power goes back on, the 1000+W load + whatever the UPS uses to charge the Li battery pack, might blow the fuse; as Li batteries can have high charge currents (charge much quicker than Lead Acid).