I’m looking to buy ups as I have few power outage (last between 1 to 5 seconds max) where I live but I have never used one so don’t know what specs should I check for
Ideally I will plug my 3d printer (about 100-160w when printing), a pi 4 with nvme drive (no idea of wattage) and a mini pc with n100 processor (around 10-20W)
Thanks for your advices
My experience has been that current UPSes tend to give a pretty limited runtime, more-limited than you might think, and are surprisingly-expensive for the capacity that they do provide.
The reason one historically really wanted a home UPS wasn’t necessarily to run a machine through a power outage, but to provide time to save any work and shut that machine down. We used to use filesystems that could become corrupt if they weren’t brought down cleanly. You could maybe run a machine for minutes, not many hours.
So it was important to warn (and maybe auto-shut down). UPSes are good at that. You have beeping alarms, software to auto-shut-down a machine cleanly when the battery gets low if someone isn’t around, software to notify a single attached computer about the battery level.
But with the combination of filesystems that don’t do that plus software that auto-saves, that’s less critical. What I think most people want is just more runtime, having a shot at making it through short power losses.
I think that today, if I wanted to provide longer-running resistance to power outages, I’d probably look at one of two things:
For a device or two, “power stations”. These sometimes get called “solar generators”, despite not generating anything, because manufacturers are marketing them as an alternative to gasoline/diesel generators for power outages. All-in-one box with batteries, charge controller, and inverter in one little case. This kind of thing. They won’t beep to warn you that the power is out, and they won’t have software (or interface) to tell a computer to automatically shut down.
For larger capacity, a “grid tie solar system”. These tend to be extensible, with separate 12V (or 24V or 48V) batteries or the like and separate boxes for the battery charge controller and inverter. You don’t actually need to hook any solar panels or other power sources up to it (though, hey, maybe you decide that you want to do so), as the battery charge controller will charge the batteries from the grid as long as the grid is providing power. You can select a size for and replace the batteries and inverter and charge controller separately, and you aren’t constrained to use a single vendor for all the components.
I would look to see that the inverter in question provides “pure sine” output. Some inexpensive inverters provide a square wave, and some devices don’t much like this.
EDIT: Ah, just saw your new comment:
You may not care about keeping the system running through longer outages, then, unless you’re also worried about longer ones.
This is absolutely the correct information. I sold UPSs for years and the general consensus is that if you want more than 5 to 10 minutes of power, then you want to go with an actual generator solution
Saying that, UPSs tend to be used in industrial environments to keep machinery running until the generator starts up and can accept the load.
And in the case of a 3d printer after so many seconds of now power what id use one for would be to cut off the bed and hotend, list the head and then run the part cooling fan full blast until power went out.
The print would be ruined but less likely to have heat creep and jams when the power goes out leaving the existing melted plastic to wick up into the heat break when the cooling fan goes out. And less likely, but technically possibly, the nozzle, still not sitting on one piece of plastic with enough heat to scorch or worse.
Yeah, I only care to keep the printer running for just a few seconds but thanks for the input
Computers and 3D printers use switch mode power supplies. They don’t care if the inverter provides a square wave or a sine wave.
What sort of grid-tie systems are you thinking of?
I ask because I’ve been considering something like that and am finding nothing but things which have an internet connection back to the manufacturer. Some US states apparently prohibit charging batteries via the grid outside of certain scenarios. Abiding by that is fine, I’m not going to charge illegally. But I’d still like a device that is 100% not controlled remotely by some other party.
My Fronius Symo Gen 24 plus could run without a connection to the manufacturer and has local APIs for everything.
Thank you!