Every time someone in r/homelab asks which UPS to buy for their first NAS, the thread collapses into the same three-way fight: APC is the standard, CyberPower is the value pick, Eaton is what the real data centers use. Everybody is a little right. Nobody explains what actually changes when the lights go out at 2 a.m. and your array needs to shut down cleanly.
I have run all three brands in my own racks and closets over the years. This post is the brand-level comparison: what it is like to live with each one, how well it plays with NUT and the NAS operating systems, how painful the battery swap is, and the single model from each brand I would buy today.
If you have not sized your load yet, do that first with my UPS for NAS and home server guide. It covers measuring watts and wiring up graceful shutdown. This post assumes you know you need roughly a 1500 VA unit and now you are choosing a logo.
What Actually Matters for a Home Lab UPS
Brand loyalty aside, only five things decide whether a UPS is good for a NAS:
- Sine wave output on battery. Active PFC power supplies in NAS boxes and servers can misbehave on a stepped approximation. All three of my picks below are true sine wave.
- NUT compatibility over USB. The UPS must report “on battery” and “low battery” so your NAS can shut down. If it cannot do that reliably, it is just an expensive power strip.
- Battery replacement. You will replace the battery every three to five years. A UPS that uses common sealed lead acid blocks and has a front or bottom battery door is far nicer to own.
- Noise. A UPS in an office or living room closet must not whine, click, or run a fan all day.
- Real runtime at your load. Not the box number at full load, but the minutes you get at the 100 to 200 watts a typical NAS, switch, and router draw.
Everything below is a judgment on those five, from living with these units, not from reading spec sheets.
CyberPower: The Value Pick That Just Works
The CyberPower CP1500PFCLCD is the UPS I see most often in home lab photos, and for good reason. It is a 1500 VA, 1000 watt line interactive unit with true sine wave output, an LCD that shows load and estimated runtime, and a price that usually lands well under the APC equivalent.
On NUT it is boring in the best way. Plug in USB, and Synology, TrueNAS, Unraid, and the usbhid-ups driver on Linux all see it as a standard HID power device. Battery charge, runtime, load percent, and input voltage all report correctly. I have never had to tweak a driver flag.
The battery story is good. It uses standard 12 volt sealed lead acid blocks, and CyberPower sells a matching replacement cartridge, but generic batteries of the same size and terminal type also fit. The swap takes about ten minutes with a screwdriver.
The weak spots: the fan on the PFC models can spin up under load and is audible in a quiet room, and the beeper is loud until you mute it in the menu. Build quality is fine, not premium. Plastic, a little flex.
Best for: first NAS, budget-conscious labs, anyone who wants the most runtime per dollar.
APC: The Default Everyone Supports
APC is the brand every piece of software was tested against first. The APC Back-UPS Pro BR1500MS2 is the current 1500 VA sine wave desktop model, with an LCD, USB-A and USB-C charging ports on the front, and a battery door you can open without unplugging the whole unit from the wall.
NUT support is excellent over USB HID, and APC has the deepest bench of alternative tooling: apcupsd still works on many models and plenty of older scripts and dashboards assume an APC unit. If you ever hit a weird edge case, someone on a forum has already posted the fix for an APC.
The trade-offs are price and the occasional firmware surprise. For roughly the same capacity, APC usually costs more than CyberPower. Some newer APC models have shipped with communication modes that older NUT versions did not handle cleanly, so make sure your NAS is on a current release before you assume the UPS is broken. Replacement batteries are easy to find, though APC branded cartridges are pricey compared with generic blocks.
Fan noise is generally lower than the CyberPower under light load, and the self-test click is quieter. Resale value is also the best of the three, which matters if you upgrade to a rack unit later.
Best for: people who want the safest compatibility bet and do not mind paying a little extra for it.
Eaton: The Quiet Premium Pick
Eaton is the brand I trust most for build quality. The Eaton 5SC1500 is a line interactive, true sine wave unit built like small business gear, because that is what it is. The case is sturdier, the transfer to battery is clean, and under typical home lab loads it is the quietest of the three in my experience.
On NUT, Eaton is a first-class citizen. Eaton has historically contributed to the NUT project, and its USB HID implementation reports detailed status reliably. Synology and TrueNAS recognize it without fuss. If you want to grow into a network management card later, the higher end Eaton lines support that too.
The downside is cost. For the same VA rating you pay noticeably more than CyberPower, sometimes close to double, and you do not get more runtime for that money. You get better parts, a quieter box, and a more robust feeling unit. Battery replacement is straightforward with a front access door, but genuine Eaton cartridges are not cheap.
Best for: labs in living spaces where noise matters, people who want gear that feels like it will last a decade, and anyone already invested in Eaton at work.
Side by Side
| CyberPower CP1500PFCLCD | APC BR1500MS2 | Eaton 5SC1500 | |
|---|---|---|---|
| Output on battery | True sine | True sine | True sine |
| NUT over USB | Plug and play | Plug and play | Plug and play |
| Relative price | Lowest | Middle | Highest |
| Noise at light load | Fan can be audible | Quiet | Quietest |
| Battery swap | Easy, generic blocks fit | Easy, front door | Easy, front door |
| Build quality | Fine | Good | Best |
Runtime is roughly comparable across all three at the same VA and battery size. At a 150 watt load, expect somewhere in the 15 to 25 minute range for a 1500 VA desktop unit, which is far more than you need to shut a NAS down cleanly. Measure your actual draw with a Kill A Watt meter rather than trusting nameplate numbers.
The Part That Matters More Than the Logo
Here is the uncomfortable truth from every outage I have sat through: the brand matters far less than whether the shutdown chain actually works. A $600 Eaton that is not wired to anything protects your array exactly as well as no UPS at all once the battery runs flat.
Whatever you buy, do these three things the day it arrives:
- Connect USB to the machine that matters most, usually the NAS, and enable its UPS service. Set it to shut down after a fixed time on battery, such as two or three minutes, not at low battery. Short outages ride through; long ones end cleanly with plenty of margin.
- Share the status over the network so other machines follow. My NUT graceful shutdown guide walks through a NUT server with a Proxmox host and a mini PC as clients.
- Pull the plug and watch. Unplug the UPS from the wall with everything running and confirm the NAS starts its shutdown on schedule. A test you never ran is a guess.
Then add it to Home Assistant so you get a phone alert when the house goes on battery. I covered that in monitoring a UPS in Home Assistant with NUT. Finally, schedule a battery self test every quarter. My UPS battery test routine shows how to catch a fading battery before the next storm does.
What About LiFePO4?
A few newer units and power stations use lithium iron phosphate batteries that last far longer than lead acid. They are tempting, especially the ones with a ten year battery claim. For a NAS, I still prefer a classic line interactive UPS with proper USB HID reporting, because many lithium power stations do not expose clean on-battery signals to NUT. I dug into that trade-off in LiFePO4 UPS for a home lab: worth it?.
The Bottom Line
If you just want the answer: buy the CyberPower CP1500PFCLCD. It is true sine wave, plays perfectly with NUT, uses cheap common batteries, and costs the least. It is my clear winner for a first home lab UPS.
Pick the APC BR1500MS2 if you want the most widely supported option and better resale, and the Eaton 5SC1500 if the UPS lives somewhere quiet and you value build quality over price. Any of the three will protect your NAS, as long as you wire up the shutdown and test it with the plug pulled.