obsidianram
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ALT - Power Source Question

Sun Apr 14, 2019 9:23 pm

Has anyone tried implementing wireless charger technology as a power source for their RPi / Pi_Monitor setup? I've been able to find a few models that have a 5W to 7W and/or 2A output, which is in the ballpark. Reason I ask is occasionally I get the dreaded lightning bolt on my 3 B+ with 7" screen setup, despite using the "official" power supply. Using a wireless charger would, I think, spare the micro connections on both devices as well as provide equal stable power to both devices simultaneously.

Any feedback would be greatly appreciated...

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Imperf3kt
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Re: ALT - Power Source Question

Sun Apr 14, 2019 9:27 pm

I think you might want to research wireless charging a bit better. Most commercially available "wireless chargers" do not work more than 10 cm away from the charge pad and all are very inefficient.
A 2A output would generate a lot of heat.

Which "official" power supply do you have? Can you link it?
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drgeoff
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Re: ALT - Power Source Question

Sun Apr 14, 2019 9:33 pm

Imperf3kt wrote:
Sun Apr 14, 2019 9:27 pm
I think you might want to research wireless charging a bit better. Most commercially available "wireless chargers" do not work more than 10 cm away from the charge pad and all are very inefficient.
A 2A output would generate a lot of heat.

Which "official" power supply do you have? Can you link it?
10 cm? More like 10 mm.

drgeoff
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Re: ALT - Power Source Question

Sun Apr 14, 2019 9:40 pm

obsidianram wrote:
Sun Apr 14, 2019 9:23 pm
Has anyone tried implementing wireless charger technology as a power source for their RPi / Pi_Monitor setup? I've been able to find a few models that have a 5W to 7W and/or 2A output, which is in the ballpark. Reason I ask is occasionally I get the dreaded lightning bolt on my 3 B+ with 7" screen setup, despite using the "official" power supply. Using a wireless charger would, I think, spare the micro connections on both devices as well as provide equal stable power to both devices simultaneously.

Any feedback would be greatly appreciated...
I don't understand your "Using a wireless charger would, I think, spare the micro connections on both devices ". You need wireless receiving stuff which neither a RPi nor screen have built in. So you have to add that and physically wire it to the screen and/or display. How is that different in terms of connections to wiring in a conventional power supply?

Nor do I understand why you think that it would be preferable in terms of stability.

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Imperf3kt
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Re: ALT - Power Source Question

Sun Apr 14, 2019 9:52 pm

drgeoff wrote:
Sun Apr 14, 2019 9:33 pm
Imperf3kt wrote:
Sun Apr 14, 2019 9:27 pm
I think you might want to research wireless charging a bit better. Most commercially available "wireless chargers" do not work more than 10 cm away from the charge pad and all are very inefficient.
A 2A output would generate a lot of heat.

Which "official" power supply do you have? Can you link it?
10 cm? More like 10 mm.
Yes, my mistake there, I indeed meant 10mm. Wasn't thinking when I typed it in.

Although that's not to say it's impossible, just depends on the technology used.
There is, for example, wattUp, capable of powering devices from up to 5M away (0.9M recommended)
https://www.tomshardware.com/news/wattu ... 36183.html
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LTolledo
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Re: ALT - Power Source Question

Sun Apr 14, 2019 10:26 pm

Requires hacking the power input side of the RPi, with considerable soldering skills..

and as stated, at the moment it is:
1. costly and cumbersome
2. inefficient
3. impractical

maybe it'll work for the Raspberry Pi Zero series, but I doubt will will work efficiently and effectively on any higher model RPi

a image/picture of your "official" power supply powering your RPi can give us a hint of your problem....
"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"

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obsidianram
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Re: ALT - Power Source Question

Wed Apr 17, 2019 4:44 am

Apologies on the delay getting back to this . . .

The PS I'm currently using is a CanaKit (5V / 2.5A - Model DCAR-052A5) with RPi 3 B+ & 7" Pi screen.
Just ordered another 3B+ and 2B+ from Adafruit along with 2 x PS (5.25V / 2.5A - Model GEO151UB--6025),
but have yet to put those into testing. The difference in cords is obviously noticeable, with the Adafruit utilizing
larger gauge wires (and probably yielding significantly better results). More to follow . . .

As for the wireless PS, yes, as I read more, I started to see the potential for the heat issue ~ and heat is no bueno
with electronics. Anywho, I was merely brainstorming alternative ideas on power sources other than solar, batteries,
or AC. That was just one that came to mind. Thanks for the feedback, Imperf3kt & LTolledo - much appreciated.

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Imperf3kt
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Re: ALT - Power Source Question

Wed Apr 17, 2019 5:14 am

Yes, unfortunately the canakit power supply has a reputation for not being too good.
A lot of people mistake it for the official power supply because it is sold as part of a kit, but it is in fact 3rd party.

There is only one (well two) official power supply, manufactured by Stontronics. It has a non-detachable cable utilising large 18AWG wiring and sports a Raspberry Pi logo embossed into the case.

You can find it via the 'buy' tag ay the top of this page, should you ever decide to try it.
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W. H. Heydt
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Re: ALT - Power Source Question

Wed Apr 17, 2019 5:35 am

obsidianram wrote:
Wed Apr 17, 2019 4:44 am
...2B+ ...
No such thing. Perhaps you mean Pi2Bv1.2?

obsidianram
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Re: ALT - Power Source Question

Wed Apr 17, 2019 8:23 am

3A+ to be exact...ooops. Also, the Adafruit PS comes with 20 AWG wiring, just FYI ~ not too terrible. I like the PS from the link above.
Raspberry Pi Universal Power Supply ~ comes with U.S. and European adapters (110 / 220 ) which none others do (IIRC). Bonus come travel & vacation time!

So what is the best viable power option when in a location without a wall outlet to plug an AC adapter into? I saw a chart somewhere of four different Pi models with their power draws listed (at idle and at load)...have to go back and see if I bookmarked it (on another system).

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Imperf3kt
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Re: ALT - Power Source Question

Wed Apr 17, 2019 8:34 am

obsidianram wrote:
Wed Apr 17, 2019 8:23 am
I saw a chart somewhere of four different Pi models with their power draws listed (at idle and at load)...have to go back and see if I bookmarked it (on another system).
That would probably be this page, about halfway down
https://www.raspberrypi.org/documentation/faqs/#power
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obsidianram
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Re: ALT - Power Source Question

Wed Apr 17, 2019 3:46 pm

Bingo ~ thanks again.

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