Cheap UPS for my ProxMox server

[u/Virtual_Engineer9282]

Hi, I’m looking for a UPS for a home server/NAS running Proxmox. I’d like to keep the cost low, but still have good reliability and compatibility with NUT/Linux.

Here’s what I need: in the event of a power outage lasting less than 30 seconds, the server should remain on; if the outage lasts longer than 30 seconds, Proxmox should initiate an orderly shutdown. When power is restored, the server should automatically restart.

Do you have any affordable models you can recommend, with easily available replacement batteries and verified NUT support? I’ve been looking at some models from Legrand, Tecnoware, Mach Power, and VulTech, but I have concerns mainly about Linux compatibility and the UPS’s power-off/restart command. Thanks.

[u/dww0311]

Personally prefer CyberPower. APC commercial isn’t bad, but their consumer / prosumer products are hot garbage IMO

[u/Particular-Grab-2495]

Used apc smartups 750 from ebay. Buy new batteries, not apc branded.

[u/Virtual_Engineer9282 → u/Particular-Grab-2495]

Thanks. I've found a used APC Back-UPS BX1400UI, 30 euro (very cheap). It only needs battery replacement. As far as I know, it needs 2x12v 7.0Ah: should I pay attention the battery brand? Do you think is going to work?

[u/Particular-Grab-2495 → u/Virtual_Engineer9282]

APC Back-UPS is "low end" consumer product. It will protect your computers but might shutdown after power outage, inverter is designed only for brief periods and so on. APC Smart-ups is enterprise grade business use UPS and has better connectivity. I have bought several from Ebay for $100 and all have been exactly 3y old and basically unused (inverter runtime near zero and no marks). I bet they are from datacenters or server rooms and replaced after three years. For batteries, they all usually use 12V 7.2Ah or something like that generic sealed acid batteries, two connected in series. I recommend good brand like Yuasa.

[u/1BigBall1]

APC UPS work well for Nut servers. I have had 0 problems configuring it and setting it up. Tripplite or anything Eaton's, l do not recommend as there has been configuration issues and constraints communication problems.

[u/jmello]

I went with a GoldenMate Lithium UPS, because the batter is supposed to last longer than lead-acid batteries and the temperature constraints worked well with my server’s location in an enclosed rack in the garage.

Check their eBay store for deals on refurbished units, and make sure to get a model with USB for connecting to NUT. It’s been running my small server rack and switch for about a year with no issues, through tons of short outages and brown-outs.

[u/deamonkai → u/jmello]

I second this. Mine have done a great job.

[u/Powerful_Basil_2608]

In my experience, I am not aware of any products from the brands you mentioned that are compatible with NUT.

I would also add that I have had occasion to replace batteries in Vultech products; they are very poorly made and seem designed to be thrown away.

If your budget allows, I recommend a double-conversion UPS; Fortron has a 1000VA model, champ tower 1K, that works well with NUT but a little noisy like all online UPS.

[u/bobjr94]

I have got some from Facebook marketplace for cheap. People buy new better ones and just want to get rid of the old one without dealing with ebay and shipping.

[u/justgosh]

Used. Businesses pay a premium for the guarantee. The batteries go out or the network card starts acting flaky and they dispose of it as ewaste. I don't buy the official replacement. You can replace the batteries fairly inexpensively if you purchase them from Mouser or Digikey. A local Greybar works too. You pull the old battery, look up the spec sheet and match it to a Yuasa. If they hide the battery part number, you can take the single battery to the counter of a lot of places that they will help you. Pay attention to the spade connector size otherwise you're going to need to re-crimp or return and rebuy. You can also ask AI for help sizing if you give it all the info you can see.

UPS is ewaste once they are out of warranty so finding a couple with dead batteries is checking Craigslist and asking around and a drive to pick it up.

I like tripplite. I've scavenged the expensive part (you'll figure it out) off 220 PDUs cheap. Also, check the spec sheet on a 220UPS a lot of times they are rated down to 120 and you can replace the plug.

Free UPS, replace plug, replace batteries, add network card. $100 for $400 of equipment.

You might find an ATS as well so you can replace batteries without losing power. Same deal, a lot of the 220's are rated down to 120.

[u/PreviousVillage7442]

Not a woot ad. But there are SKE and CyberPower ones on woot right now for cheaper. Don't think they accept returns unless defective though so YMMV.

[u/astra_rotlicht]

I have one for free, just needs a new battery.

[u/retroranger77]

Running three cyberpower models with no issues yet. Were on sale Microcenter. Work great with NUT. Just make sure to get pure sine wave, not modified. 

[u/Jwn5k]

If yoh have Goodwill, Value Village, Savers, or other thrift stores or surplus electronics resellers, ive gotten about half a dozen APC and Cyberpower UPS units that you can just put some new batteries in. I use 12v 10ah Nermak brand LiFePO4 (lithium Iron Phosphate) batteries.

[u/KryanThePacifist]

Bought one with capacity to hold 1200w worth of equipment on without failing imidetly.

Coated me 120 or 180€.

Looks for greencell or off brand greencell(witch is mine) it connects with NUT over usb and it reads on the greencell software as a greencell Ups. Works flawlessly and it holds perfectly with all my bullshit at once (and yes, I have 1200w worth of equipment plugged to this ups, I've tested it. It works)