RPi5 - power issues

[cleggers21]

I guess there’s no simple answer to my issue but perhaps it may be a warning to others.
I went for the latest Pi5 8G.
I first connected it to a TalentCell @ 5v x 2A to test and it worked fine with a zwo cam.
I then got a cheap buck converter dropping 19v x 5A AC power block to its advertised 5v x 5A and it kept erroring with ‘low voltage’ and cutting out, now using the Pi HQ cam.
I then got the official Pi5 5A power block which worked fine until I added a 2m USB3.3 (100W) extension cable and it again it errored and cut out once after 24 hours.
I’m now wishing I’d gone for the Pi4 with its lower power requirements.
I note #3383 suggests POE which may be the only solution unless I source an even higher power block over 5A.
Unless there’s a way of reducing the power requirements of the Pi5 ?

[EricClaeys]

I don't know. Perhaps Google does, or a post on the Raspberry Pi forum?

[cleggers21]

Thanks Eric, I can't find anything on the RPi forum for the Pi5 well know power lead extenstion issue.

[astrotater]

What is the voltage at the Pi itself? In the past, if I have a long cable run, I'll up the voltage to the Pi (I was using a Pi 4) to something around 5.15v to account for V drop.
My new design I'm working on has DC input to the case of 13.6V, and I have a converter inside the case to drop it to 5V/5A, so V drop won't be an issue anymore.

[cleggers21]

The Pi Hut sell a 2m extension for the RPi4 but not the Pi 5 so I guess that’s acknowledging the drop of V over such a distance.
I tried a buck converter rated at 5A but it failed so if your going for a converter I suggest you make sure others have had success with the converter you choose.

[cleggers21]

Just been reading the Pi forum which suggests when the V drops it throttles the CPU so fast that a human would not be able to see the drop. I considered throttleing back the CPU speed but it appears the 5 dosent support this option. Unless someone knows better ?

[astrotater]

This might work. Pololu makes high quality stuff. I have one that I'm going to test with the Pi5. I have a Pi5 and a Pimoroni NVME base that should be here by the end of this week that I want to test with the D24V50F5.

https://www.pololu.com/product/2851

[cleggers21]

Fingers crossed then, please let me know how you get on.

The one I got was only £5.

[mottld]

I have found all the cheap power supplies quarky with tthe PI 5. I switched to a poe+ splitter with 5v type c out and havent had any problems since. I have an active cooler, nvme and ASI676mc running on it. If you dont have a poe switch, you could use a poe+ injector.

[cleggers21]

Thanks
I’ve ordered another buck converter- 8A with adjustable output V so will give that a go on Wednesday. If it doesn’t work I’ll look at Poe.

[mottld]

I also tried the POE hat for the PI5 and ran into throttling issues as well.

[EricClaeys]

@mottld, which PoE HAT did you use? I have one Waveshare PoE HAT for a Pi 5 and am waiting to see what Raspberry Pi comes out with before getting more.

[mottld]

@EricClaeys I had the Waveshare for the PI5 too. It didn't like all the accessories plugged in, especially the HQ cam I started with. I dont think they have a big enough cap on the ps output, so under a load, voltage would dip momentarily. So I switched to the poe splitter and can monitor the power draw from my switch. It only averages 5-6 watts. Every once in a while it will peak to 9.8 watts. Probably an edge case in the monitoring of the power.

[Alex-developer]

I guess there’s no simple answer to my issue but perhaps it may be a warning to others. I went for the latest Pi5 8G. I first connected it to a TalentCell @ 5v x 2A to test and it worked fine with a zwo cam. I then got a cheap buck converter dropping 19v x 5A AC power block to its advertised 5v x 5A and it kept erroring with ‘low voltage’ and cutting out, now using the Pi HQ cam. I then got the official Pi5 5A power block which worked fine until I added a 2m USB3.3 (100W) extension cable and it again it errored and cut out once after 24 hours. I’m now wishing I’d gone for the Pi4 with its lower power requirements. I note #3383 suggests POE which may be the only solution unless I source an even higher power block over 5A. Unless there’s a way of reducing the power requirements of the Pi5 ?

I had exactly the same issue but did solve it. The setup here is

• 178MM 10m up a pole
• 12v Dew Heater
• All hardware, except the camera!, in a box at the bottom of the pole.
• Hardware is fed by a 12v 10A PSU

I too used the 'cheap' buck converters and quite frankly the are rubbish ! ended up using this convertor which as worked fine

https://www.amazon.co.uk/gp/product/B08PFL7VVN

[cleggers21]

Thanks Alex, fingers crossed the new buck I’ve ordered will work.

[bendenajones]

I also had pwr issues with my RaspPi 5 4MB, Pi Cam, dew heaters, exhaust fan setup. None of my existing 120v to DC 5 volt converters could hold 5.0V under load. Using a voltmeter and Pi "load testing" scripts I adjusted the output of my 12v power supply noted below. I did not run fan or heaters directly off Pi but they used the same power input.

There are many stress testers out there; here is one

This power supply is small w/ an adjustable pot that enables one to increase the voltage output until stable under load.

One could use the stress test w/ pi in enclosure to make sure cooling is sufficient to prevent throttling as well.

[Alex-developer]

I also had pwr issues with my RaspPi 5 4MB, Pi Cam, dew heaters, exhaust fan setup. None of my existing 120v to DC 5 volt converters could hold 5.0V under load. Using a voltmeter and Pi "load testing" scripts I adjusted the output of my 12v power supply noted below. I did not run fan or heaters directly off Pi but they used the same power input.

There are many stress testers out there; here is one

This power supply is small w/ an adjustable pot that enables one to increase the voltage output until stable under load.

One could use the stress test w/ pi in enclosure to make sure cooling is sufficient to prevent throttling as well.

Pretty much the same issues I had. Getting a stable 5v under load was nearly impossible, I was using cheap buck convertors. The one I posted above maintains 5v perfectly even under severe load

Alex

[cleggers21]

Bugger
https://thepihut.com/products/pd-power-extension-board-for-raspberry-pi-5

[cleggers21]

Short answer is I don’t know.
When I read it last night I picked up on the ‘DC 9-24v input’ printed on the board and USB 3 5v x 5A output. So I guessed it’s a sophisticated buck converter which would allow me to use an old laptop 19v power block so getting over the ‘long usb cable’ restriction. However the description doesn’t match as it says exact DC TBC shortly.
It also mentions ‘ Supports automatic startup of the Raspberry Pi upon power restoration’ I don’t know if this solves a problem or not.

[Alex-developer]

Bugger https://thepihut.com/products/pd-power-extension-board-for-raspberry-pi-5

I have one coming tomorrow so will let you know if it works

[cleggers21]

This chain may be of interest although it’s getting to the edge of my understanding.
https://forum.dronebotworkshop.com/raspberry-pi/raspberry-pi-5-dc-dc-buck-down-power-supply-from-36v-best-method/paged/4/#:~:text=The%20Raspberry%20Pi%205%20will,supplies%20do%20not%20supply%20this.

[astrotater]

Bugger https://thepihut.com/products/pd-power-extension-board-for-raspberry-pi-5

I just bought this one. It should be here Monday. Looks the the cleanest, most reliable way of getting power to the Pi5 in my remote enclosure.

[Alex-developer]

MIne has arrived - Looks good and will test it in the next few days

[cleggers21]

Just an update from me, got another buck converter but with a pot to adjust the output. Good stable output using a 19v old laptop psu and long cable BUT the pot is so sensitive that you just have to touch it and it whizzes up to 6v so too risky to use. Waiting to see how #Alex-developer gets on with the Pi Hut converter.

[astrotater]

Just an update from me, got another buck converter but with a pot to adjust the output. Good stable output using a 19v old laptop psu and long cable BUT the pot is so sensitive that you just have to touch it and it whizzes up to 6v so too risky to use. Waiting to see how #Alex-developer gets on with the Pi Hut converter.

Got my 52Pi Pi5 DC to USB PD converter. But, it doesn't use a standard barrel jack. I believe it's a 4mm O.D. barrel jack, so I'm waiting for one of those to be delivered until I can fully test my power board.

[astrotater]

The 52Pi Raspberry Pi 5 power board works great, installed it and ran it last night, zero power issues or low voltage warnings. Highly recommend.
https://52pi.com/products/52pi-pd-power-extension-adapter-board-for-raspberry-pi-5

[cleggers21]

Great news. Can you confirm what you are powering the converter with?
The Pi Shop description says 9-12v input but the board legend says 9-24v. The Pi shop are clarifying from their supplier.

[astrotater]

13.6'ish volts from a 400ah LiPo battery bank in a solar powered observatory.
It fluctuates depending on charge level, but thats usually where it hangs out.

[cleggers21]

👍

[cleggers21]

In closing this thread FYI I ended up using the https://wiki.52pi.com/index.php?title=EP-0225 board with an old laptop 19v power brick. This enabled me to have a 5m power cable.

[jsalsburg]

I may be repeating something already posted but the RPi5 has a new power supply system unlike its predecessors. The "Certified" power bricks for the RPi5 are not the usual wall warts. They communicate with the new power circuits on the RPi5 in both directions. At Boot time, the RPi5 interrogates through the USB type C power connector to establish if the power brick is intelligent or not. By connecting a Buck-Boost converter to the RPi5 power connector, the RPi5 will boot without the annoying low power throttling status after booting by adjusting the power to 5.2 VDC or even higher. The Buck-Boost converter must be able to sustain 4 Amps (5 Amps is better) to prevent the RPi5 from throttling after boot time.

[chvvkumar]

Just saw this thread and thought I'd chime in. The Pi5 uses normal Type-C PD negotiation but, in their effort to cut down cost of power circuitry on board, the Pi foundation went with the less common 5V5A profile. This profile, while is according to the standard, is not normally common in many Type-C chargers. Only one of my five LiFePO4 power stations support it. The others complain when a Pi5 is plugged-in.

So in essence, you need to make sure the Type-C power supply supports 5V5A profile for properly supporting the Pi5.