If you put a bunch of computers in charge of your house, it’s generally desirable to ensure their up-time is as close to 100% as possible. An uninterruptible power supply can help in this regard. To that end, that’s why [Bill Collis] whipped one up for his Home Assistant setup.
[Bill]’s UPS is charged with one job—keeping the Home Assistant Green hub and an Xfinity XB7 cable modem online when the grid goes dark. The construction is relatively straightforward. When the grid is up, everything is powered via a Mean Well AC-DC 12 V power supply, while the power is also used to charge a 12.8 V 10 Ah lithium iron phosphate battery pack. When the grid goes out, the system switches over to running the attached hardware on pure battery power. A Victron BatteryProtect is used to automatically disconnect the load if the battery voltage drops too low. Meanwhile, a Shelly Plus Uni module is used to monitor battery voltage and system status, integrated right into Home Assistant itself.
If you want to keep the basics of your smart home going at all times, something like this is a pretty simple way to go. We’ve featured some other great UPS builds in the past, too. If you’re whipping up your own hardware to keep your home or lab alive in the dark of night, don’t hesitate to notify the tipsline.
Did anybody ever build an ups using multiple powerbanks ?
Meanwhile, my slightly extended (with a power bank) picoPSU 😅
I made my old laptop a home server. It has a 2TB drive, and 16GB of RAM, and I run HomeAssistant, a SMB file server, Syncthing and a 7B LLM on it. If you have an old laptop, better to use that as a home server than messing around with a UPS or battery
I have made a DIY UPS for my raspi zero 2W server though, with a 4Ahr lithium cell. It has auto switchover and its incredibly robust, despite being made from a TP4056 module, a boost converter and a single AO3401 FET. It can charge the cell while also powering the board (battery is disconnected, in such a case). Whenever power goes away, it immediately uses the cell to make 5V
you can buy what you built for 99 cents on Ali. little modules that take two 18650 and offer 5, 9 or 12V output. they include charge control and discharge protection
The battery pack in my laptop became swollen so I just switched to a sbc solution and gave up on ups.
you can buy 12V UPSs for less than the cost of the wagos used in this project. you can get them “straight to mains” with uninterruptible 12V output, or as PCBs with USB-C input and 5-9-12V outputs (these cost 99 cents on Ali)
one really needs to choose battles properly and hacking something together for $100+ providing no real benefit over a $20 solution is just silly.
My guess is that he did choose his battles and decided it would be fun to roll his own. That’s what I do.
Sure but his setup will keep him online twice as long and probably last a decade or more before he needs to buy a new battery. Then it will be like new after that. The rest of the device could outlive him.
99¢?
Suggestion, if you are going to use something that cheap then get yourself a nice big tub. Fill it half with sand. Place your 99¢ device in the middle of the sand so it cannot contact anything flammable when it goes. Then stare at it and consider your life choices.
I wonder what that “Xfinity XB7 cable modem” connects to when “mains goes out”. Cable distribution involves active amplification systems on the streets or in the basements. When “mains goes out” typically the whole street or suburb is affected. So your modem probably can not connect to anything.
You might get luckier with GPON Fiber or “Internet via Mobile” (UMTS, 3G, LTE, HSDPA, 4G, 5G, whatever it is called these days)
Yes, GPON works through outages because that P means that the last-mile network is passive. And for $30 or so you can buy a little DC UPS with a few 18650s in it that keeps your ONT (modern) and router running for about 6 hours.
all of my network equipment is on a UPS and when the power goes out the fiber does stay online.
I would assume this is the same since the network companies are also on UPS (and possibly generators)
The network companies, yes. The distribution hub on the street, no. Even worse for Outdoor-DSLAM’s used in VDSL2 Networks, that are really power hungry. A simple UPS won’t last them long, not that it makes sense in an Outdoor rack.
Well, at least on those around here, almost half of the cabinet is used by batteries so yes, for some moderate times ( 6 hours ? half a day ? ) they will stay powered up.
i’ve never seen in-home active amplification for a cable modem. in fact it generally needs to be hooked up to the incoming coax before any active amplification to even have a hope of working.
last place i lived with cable, the big distribution box everyone kept driving their cars into was outside of the neighborhood, and while i have no idea where it was getting its power, the cable was generally working when the power went out.
Well, I can tell you it is common in Belgium. The (bidirectional) coax amplifier is installed together with the modem and both are considered the ISP part of the network.
We have the ability to replace the ISP provided modem with our own compatible device, but the ISP amplifier needs to stay in place.
Ordinary one-way amplifiers.. nope. But they make special bi-directional amplifiers for use with cable modems. We used to have to use one before the cable company replaced our drop.
I need to come up with a bingo card for comments when articles like these pop up.
nice photo
If the insurer sees them, they’re unlikely to pay out
https://www.tztstore.com/goods/show-8155.html – this is a more simple solution. as this is connected in parralel with the psu and the load. It runs on 3s Li-Ion packs. The only caveat is that you need to adjust the PSU output voltage to 12.8v to achive 100% SOC on the pack. I’m running a mini pc, router and security camera on the same 12v “bus” and it had zero issues.
Amazon Basics makes a UPS lol
No fuse? Another potpourri of modules, I guess it does the job.
What does the MOSFET ideal diode do?
Not 5 minutes ago i wrote about messages disappearing and that message vanished! There was nothing wrong with it, except it wasn’t on topic, because there is no such topic. This is ridiculous! What is this?!
This whole comment chain disappeared for several hours at least, so I’m guessing a technical issue.
Hmmm.. backup power on a cable modem?
Many years ago I worked tech support for a large cable internet provider.
During power outages we would get angry customers calling in.
Most had backup power for their computers and modems.
They expected all our systems to be on backup power too, all the way from the office to the farthest out in the sticks single home endpoint.
A few didn’t seem to understand the concept of electricity at all and just called when they pushed the button and the computer did not turn on.
Neither were any fun.
The company did have backup generators in places but not everywhere.
As corporations are, their focus was on maximum profit and they did not have generators everywhere.
I was there for the northeast blackout of 03. Millions were without power for days. People had difficulties finding gas for their cars and generators because most gas stations had no generators of their own. Boil water advisories were everywhere because pumps were not working. Hospitals were in danger of losing patients.
And yet… people were ANGRY that their internet was down. And it wasn’t even as integral a part of life as today! It amazed me to see people’s expectations.
Company talking points were that it was an entertainment service and if they NEEDED reliability guarantees then they needed to spring for the business class service… which besides being far more expensive was not available in most areas. No doubt the availability was related to the buildout (or lack of) of generators!
Few customers were made happy by the talking points but what can one do but what the people writing the paychecks say to do?