subtlenv
Posts: 8
Joined: Sat Sep 15, 2018 3:04 pm

33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Wed Jun 16, 2021 2:29 pm

Let me provide a little background for my title.

One morning I woke up and the Raspberry PI was dead, well not the PI but yeah. There were some thunderstorms previous night. And I felt that it might have fried my PI. But that wasn't the case. My power adapter that came in the Raspberry PI Kit was dead, I confirmed it.

Fast forward a few days. I tried to use my 2AMP rated 5v smartphone adapter to power it up. But the lights went haywire still I could technically use my pi but the lights would come and go like it's about to go out. I pulled the plug and didn't use it again.

Fast forward more few days, the present day. I got a charger that had a 3AMP @ 6v and 1.5AMP @ 12v rating. So I've been using it to power my PI up and everything looks good except my mental state.

I know I should get a proper adapter but due to covid and stuffs I cannot get anything to buy. Also, I am using PI as a bridge so I'm desperate to keep using it.

My question is: Will it affect my PI ? And should I continue using it ? And why in the world does a smartphone charger have multiple output ratings ? And most importantly how does it know when to supply what amount ?

wildfire
Posts: 813
Joined: Sat Sep 03, 2016 10:39 am
Location: Dundee, Scotland

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Wed Jun 16, 2021 2:37 pm

It's been repeated often on here "a charger is not a PSU".

I'd say you've been lucky so far but feeding 6V to your Pi won't end well. Get a PSU as soon as you can.
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Still NF Shirls

trejan
Posts: 3344
Joined: Tue Jul 02, 2019 2:28 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Wed Jun 16, 2021 4:31 pm

wildfire wrote:
Wed Jun 16, 2021 2:37 pm
I'd say you've been lucky so far but feeding 6V to your Pi won't end well. Get a PSU as soon as you can.
They're not feeding it 6V. They have a charger with QC or similar that can negotiate for a higher voltage. The non-negotiated voltage is still 5V.

trejan
Posts: 3344
Joined: Tue Jul 02, 2019 2:28 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Wed Jun 16, 2021 4:37 pm

subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
Will it affect my PI ?
No. The charger will output 5V unless told otherwise and the Pi has no ability to send the required signal for that.
subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
And should I continue using it ?
If it is stable and you don't notice any issues like the low voltage lightning bolt then you're fine to continue using it. If you're unsure still or see odd behaviour then buy one of the official Pi PSUs.
subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
And why in the world does a smartphone charger have multiple output ratings ?
The higher voltages allow more power to be delivered for faster charging of your phone/tablet/whatever.
subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
And most importantly how does it know when to supply what amount ?
The charger will have Quick Charge, USB-PD or another similar protocol. The charger will default to 5V as everything accepts that and then the device will signal to the charger that it accepts a higher voltage for faster charging.

wildfire
Posts: 813
Joined: Sat Sep 03, 2016 10:39 am
Location: Dundee, Scotland

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Wed Jun 16, 2021 4:41 pm

trejan wrote:
Wed Jun 16, 2021 4:31 pm
wildfire wrote:
Wed Jun 16, 2021 2:37 pm
I'd say you've been lucky so far but feeding 6V to your Pi won't end well. Get a PSU as soon as you can.
They're not feeding it 6V. They have a charger with QC or similar that can negotiate for a higher voltage. The non-negotiated voltage is still 5V.
I understand that trejan, but chargers have not always negotiated properly, additionally we are not aware of how this charger is being connected to the PI 3B+

As far as I know negotiable chargers use a USB-C connector (I could be wrong) the 3B+ has no such connector. With lack of information I always err on the side of caution.
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Still NF Shirls

trejan
Posts: 3344
Joined: Tue Jul 02, 2019 2:28 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Wed Jun 16, 2021 4:51 pm

wildfire wrote:
Wed Jun 16, 2021 4:41 pm
I understand that trejan, but chargers have not always negotiated properly
You're being overly cautious. OP has stated that it isn't going to be easy for them to swap it. Why cause them unnecessary worry on the tiny chance that they've got a faulty charger? If it works and is stable then there is no reason to swap it.
wildfire wrote:
Wed Jun 16, 2021 4:41 pm
As far as I know negotiable chargers use a USB-C connector (I could be wrong) the 3B+ has no such connector.
There are many other standards like Quick Charge which support micro USB.

drgeoff
Posts: 12072
Joined: Wed Jan 25, 2012 6:39 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Wed Jun 16, 2021 8:55 pm

subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
I got a charger that had a 3AMP @ 6v and 1.5AMP @ 12v rating.
Is that 6v a typo or do you really mean it?
Quis custodiet ipsos custodes?

LTolledo
Posts: 5563
Joined: Sat Mar 17, 2018 7:29 am
Location: Anime Heartland

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Wed Jun 16, 2021 9:34 pm

your mental state will return to normal until you use a proper power supply for your RPi....
no one can assure you if your mental state will recover or deteriorate further with your continued use of your charger

its your RPi
its your mental state
so.....
its your move....
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"

Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"

subtlenv
Posts: 8
Joined: Sat Sep 15, 2018 3:04 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Thu Jun 17, 2021 12:49 pm

trejan wrote:
Wed Jun 16, 2021 4:37 pm
subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
Will it affect my PI ?
No. The charger will output 5V unless told otherwise and the Pi has no ability to send the required signal for that.
subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
And should I continue using it ?
If it is stable and you don't notice any issues like the low voltage lightning bolt then you're fine to continue using it. If you're unsure still or see odd behaviour then buy one of the official Pi PSUs.
subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
And why in the world does a smartphone charger have multiple output ratings ?
The higher voltages allow more power to be delivered for faster charging of your phone/tablet/whatever.
subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
And most importantly how does it know when to supply what amount ?
The charger will have Quick Charge, USB-PD or another similar protocol. The charger will default to 5V as everything accepts that and then the device will signal to the charger that it accepts a higher voltage for faster charging.

Wow! Thanks for putting that effort in providing an answering! :)

I finally understand how everything works now.

I normally SSH into my PI as it's a headless setup. But occasionally I do a xrdp ( vnc felt slow ).

Now that you've mentioned that "low voltage". I have noticed that it has a banner as shown below. Will it cause any harm to the PI ? I mean it's low power and not over power, how bad can it get ?
Screen Shot 2021-06-17 at 18.39.00.png
Screen Shot 2021-06-17 at 18.39.00.png (58.03 KiB) Viewed 193 times
Last edited by subtlenv on Thu Jun 17, 2021 12:56 pm, edited 1 time in total.

subtlenv
Posts: 8
Joined: Sat Sep 15, 2018 3:04 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Thu Jun 17, 2021 12:51 pm

drgeoff wrote:
Wed Jun 16, 2021 8:55 pm
subtlenv wrote:
Wed Jun 16, 2021 2:29 pm
I got a charger that had a 3AMP @ 6v and 1.5AMP @ 12v rating.
Is that 6v a typo or do you really mean it?

It's not a typo. It has that written on the charger. The charger is for POCO X3.

subtlenv
Posts: 8
Joined: Sat Sep 15, 2018 3:04 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Thu Jun 17, 2021 12:56 pm

wildfire wrote:
Wed Jun 16, 2021 2:37 pm
It's been repeated often on here "a charger is not a PSU".

I'd say you've been lucky so far but feeding 6V to your Pi won't end well. Get a PSU as soon as you can.
Sure thanks, will get one as soon as I can. :)

subtlenv
Posts: 8
Joined: Sat Sep 15, 2018 3:04 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Thu Jun 17, 2021 12:58 pm

LTolledo wrote:
Wed Jun 16, 2021 9:34 pm
your mental state will return to normal until you use a proper power supply for your RPi....
no one can assure you if your mental state will recover or deteriorate further with your continued use of your charger

its your RPi
its your mental state
so.....
its your move....

Hmmmmm...

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 29048
Joined: Sat Jul 30, 2011 7:41 pm

Re: 33 Watt Smartphone Charger to Power up my RasPI 3B+. I am concerned !!

Thu Jun 17, 2021 12:59 pm

subtlenv wrote:
Thu Jun 17, 2021 12:49 pm
Now that you've mentioned that "low voltage". I have noticed that it has a banner as shown below. Will it cause any harm to the PI ? I mean it's low power and not over power, how bad can it get ?

Screen Shot 2021-06-17 at 18.39.00.png
It won't harm the Pi, but power supply issues can manifest in weird ways - unexpected crashes, SD card corruption, Ethernet dropouts etc
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Working in the Application's Team.

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