Advice for good UPS for rasberrypi 4B


I am a newbie I am trying to buy a good UPS for rasberry pi 4 B.

I am looking for following feature

  1. auto shutdown on power failure (voltage drop)
  2. Auto startup when AC supply is back.
  3. works with most version of Linux including raspbian
  4. reliable hardware and software.

I am aware of pijuice but need some alternative to it.

It will be helpful if product link is provided

Product links are difficult, because we don’t know where you live and what’s available to you.

I don’t have experience with UPS daughter boards for Raspberry Pis, but wrote this guide for installing a standalone UPS with a USB port.

I would recommend a CyberPower UPS, only because I know for certain that they work. But really, you just need any UPS that has a USB port and is known to work with Network UPS Tools. AmazonBasics is now selling units that appear to be rebranded CyberPowers. I ordered one recently, but haven’t received it yet.

I have my RPi, modem, and router all on the UPS, so that OH can notify me if there’s an outage (since it will still have Internet access). It only runs for about 10 minutes before shutting down the RPi, but that’s enough to cover most brief outages.

2 is going to depend on the hardware plugged into the UPS. What happens when they lose power and power is restored? A big challenge will be what is you lose power, the machines shut down and power is restored before the UPS loses all it’s charge?

Well for 2 what I want is when AC power is lost. the raspberry pi will run on UPS. But if its too long and there is a drop in voltage of battery of UPS. The ups should send a signal to the rasperrbypi and the rasberrypi should shutdown.

When AC power is back the rasberry pi should restart.

I hope it makes clear
Please see the product link below

But the link product is not available in my locality

That’s where it’s hard. What if the battery never went all the way off? After a shutdown, an RPi won’t restart until power is removed and then restored.

I think the UPS he links to will shutdown the RPi, when power is lost, no matter the state of the battery. (The battery is only used to make sure to get enough time to shut the RPi down).
When power returns it will start the Rpi again.

That would make sense to me.

How? The RPi is shut down at that point. Unless the UPS pulls power from the plug and powers the plug again, which in my experience would be unusual behavior, it can’t start up the RPi again. Once shut down the only way to boot the RPi up again is to pull and restore the power.

It can start the RPi again.
If you take a look at the 4. picture on amazon, there is a pin for Auto starting the RPi… I´m pretty sure it somehow shortcircut the power pins on the main RPi board, just like an ordinary PC.

Looks like it shuts down the RPi, then toggles the power when AC returns.

I’d guess that it detects the RPi’s current draw to determine if it should toggle. At least, I hope that’s the case, so that it doesn’t kill the RPi when there’s a brief flicker.

If its build correctly, it should prevent any kind of damage cause by power flickering.

The idea with this UPS is quite simple.
In case of power loss, shut down the RPi in a safe way.
When Power return, auto power (auto start) the RPi again.

This UPS is not suppose to run the RPi in several minutes/hours in a power loss enviroment at all.

Well, yeah. The question with these types of things is more “built correctly” than anything else. From that perspective, this review does not give me confidence:

It’s just one person, but “caught on fire” is usually enough for me to lose interest in a product. Mind you, I tend to avoid any high-voltage electronics that don’t have certification from the appropriate electrical authorities.

Seems like you can program it to keep the RPi going if you stack batteries, but at some point it’s going to be more effective to get a standalone UPS (and probably cost less).

  • Provides continuous operations for up to 10~30hours (depending on battery type and qty used)

Agree, this could be a lousy cheap UPS which doesnt deserve to be sold on the market. Its not uncommon for these cheap devices. And if they´re build badly, they will do more damage than any good.

I would always recommend a good and stable brand UPS like an APC or something simular. Problem with an UPS like this is, that it will not be possible to power on the RPi, as far as I know.

Well may be what is being discussed here is correct that such ups are risky but googling tells me lot of positive feedback for the concept and the circuit.

This is not only product in the market. There are many such I am posting two more links on same concept these two are very popular.

Also see the YouTube video

People are using it. I need a reliable UPS with similar functionality as auto on and off

Apart from this I am aware of another renowned DIY UPS which is based on same concept but uses high value capacitor to do the same instead of battery.

I am not finding the link now…

So coming back to the question is there any UPS in cyberpower Or APC or anyother renowned brand which can do same?

Conceptually, they’re all fine. As I stated earlier, the part I have a hard time with is trusting the quality of the materials and manufacturing. If you search the community, you’ll find others that are using UPS hats like these ones, and their risk assessments will be different from mine. Go with whatever makes you comfortable.

I’m not aware of any standalone UPS units that will do this, because they rely on the USB port to send commands. If you can’t find one, your options appear to be:

  1. Onboard UPS that connects to the RPi GPIO and has auto-start
  2. Standalone UPS that connects via USB, but doesn’t have auto-start

It really comes down to how important auto-start is to you. If it’s truly a must-have feature, then you just have to find one that you trust. I can see why you’d be concerned if you live in an area with frequent power outages. If you’re talking once or twice a year, maybe it’s not that big a deal.

At a glance, PiJuice appears to have put real effort into their website and documentation (I haven’t dug any deeper on the Amazon links). It’d be worth your time to look through their GitHub to see what users have to say and what issues they run into.

Thanks I think I would need little more time to decide on it. I will study a bit more. At the moment I more inclined towards UPS with NUTlike cyberpower my only stopping point is auto start.

Actually I am building a new house where I am automating everything but unfortuantely I wont be staying much in the house as I work in different city and my elderly parents would be staying they are not tech savy and even switching on a UPS is abit difficult. So any idea if we can automate the auto start of rspberrypi by switching off the UPS after rasberrypi shutsdown and then when power is back UPS is powered on and there by switching on the Rasberrypi.

I am also fine if I can automate the UPS switching on by using Sonoff wifi or zigbee switch even that involves opening the UPS and changing the manual switch.

The idea is before rasberrypi switches off it triggers a command through rest api to the a timer which switches off after a while

Let me know your post on same

That doesn’t make sense. You would have to use the UPS to power the Sonoff (since there would be no power from the wall outlet), so when the Sonoff turns off the UPS, nothing will be able to turn it back on.

I suppose you could instead place a Sonoff between the UPS and the RPi’s AC adapter, but then you have to account for all of the power-loss scenarios to design your start-up behaviour. Also, you run the risk of the Sonoff toggling and killing your RPi. For example, if you use Tasmota firmware, I believe the switch will toggle when you update the firmware.

For systems you can’t manage directly, simple is always better. The more complicated you make it, the more difficult it will be for your parents when things go sideways.

I would suggest just adding a power button to the RPi (with a reboot/shutdown script). If there’s an outage and nothing is automated when the power is restored, they’ll just have to push the button to turn it back on. That’s not difficult and enables them to do something to get it working. You can even leave a three-step instruction card for them.

Alternatively, you can put a cloud-controlled smart switch (e.g. a TP-Link Kasa) between the RPi and UPS, so that you can control it remotely. If there’s a power outage and you can’t reach their system through myopenHAB, you’d just have to toggle the switch. Or they can do it themselves.

I am getting more inclined towards your solution of UPS with NUT capabilities.

But unable to find an UPS which supports NUT and has low minimum load requirement.

Since rasberrypi 4 at most will draw 15 watt hence looking for UPS which will operate with such low load also has NUT compatible usb port.

I chatted with APC brand online sales department they were clueless so stuck now.

Posting the official APC product line

If someone can help choosing me one

As far as I’m aware, there’s no such thing as a minimum load requirement for a UPS.

A UPS is a power bar with a surge protector and a battery. In the same way that you plug your RPi’s AC adapter into a power bar or a wall socket, you can plug it into a UPS. That being said, I’m only familiar with North American AC power, and perhaps there’s something in India I’m not aware of. If that was the case, I assume that APC India would know about it.

Whatever the case, the simple solution is to plug more things into the UPS. As I said in my original post, I have my RPi, DSL model, and WiFi router on my UPS so that I can maintain my network for a brief period of time.

The only recommendation I have is to check if the UPS you want to buy is compatible with NUT. I don’t have an APC, so I can’t say more than that.

BTW, the 15W you mentioned is the maximum DC output of the AC adapter (5V/3A), but an RPi almost never draws that much. The extra amperage is to account for add-ons that consume additional power (e.g. a USB mouse or a GPIO shield). Similarly, mobile phones don’t charge at maximum amperage all of the time, as that would damage the batteries.

About | apcupsd comes to mind … - and is supported by NUT. :slight_smile:

Well I have been studying a lot and yes both cyberpower and APC or any other do mentions minimum load requirement in UPS.

As you would agree UPS has auto shutdown feature this is where minimum load comes into picture if UPS is not connected to the soecified minimum load than the UPS would auto shutdown within some specified time say 30 seconds

Some links to this concept there are many I am attaching 2,the%20light%20being%20always%20on.&ved=2ahUKEwijw5WTnPv1AhXozDgGHROCB8sQFnoECAQQBQ&usg=AOvVaw0PIKUyJq0XhGYw87V0s9Kh