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[nye2654321]

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[GTR2Fan]

5.35V is a little above the spec maximum of 5.25V but shouldn't do any harm. It may even fall within spec when loaded. The 2A current rating is irrelevant.

[mahjongg]

What do you mean by "handle", it needs a power source supplying 5V with a margin (precision) of 5%, so 5.35V is not within the margins, but when loaded the voltage will probably drop from 5.23V to a tenth lower, and when the voltage reaches the PI, it will be lower still because the cable has resistance too, and will consume a few millivolt, so okay.

At 6V the PI will short its input to protect itself, (and its peripherals) but 5.35V is below that by a good margin, so no problem there. Actually its not the PI itself that needs 5% precision, but the USB devices connected to it do!

As for current, as long as the source can provide what the PI needs its okay, it will use what it needs, what the power supply can deliver is irrelevant.

Naturally if you try to power the PI with submarine batteries that can deliver 500 Amperes when needed, be careful not to make any shorts.

P.S. I see my habit to write long answers again made mine the second answer... no matter, the first answer is to the point.

[W. H. Heydt]

If you decide to try it, get one of these: http://www.adafruit.com/products/185 to check the actual voltage under load. (What the Pi actually gets will be a bit lower because of cable resistance as already noted.)

[Burngate]

... http://www.adafruit.com/products/185 ...

http://www.adafruit.com/products/1852

[pluggy]

Somebody else who doesn't understand electricity. My house has a supply capable of providing 20kW, thankfully it only uses a tiny fraction of that most of the time, or I couldn't afford the bills. You could plug a 2000 amp power supply into the Pi, and it could handle it, (irrespective that you could only get about 1.5 - 1.8 amps through the micro USB connector) its just wouldn't use it. A Pi B without peripherals will use around 400 mA (0.4 amps) and a B+ and A considerably less than that.

[plugwash]

Somebody else who doesn't understand electricity. My house has a supply capable of providing 20kW, thankfully it only uses a tiny fraction of that most of the time, or I couldn't afford the bills.

It also has a load of protective devices designed to limit the risk of damage in the event of a fault.

You could plug a 2000 amp power supply into the Pi, and it could handle it, (irrespective that you could only get about 1.5 - 1.8 amps through the micro USB connector) its just wouldn't use it. A Pi B without peripherals will use around 400 mA (0.4 amps) and a B+ and A considerably less than that.

You could and if there were no faults and the power supply was no-load stable (not all are) it would work but I wouldn't reccomend it because if there was a fault then having more current available from the power supply massively increases the potential for damage.

[Joe Schmoe]

As Gert says, make sure your fire insurance is paid up.

[Bosse_B]

... http://www.adafruit.com/products/185 ...

http://www.adafruit.com/products/1852

Yeah, I wondered about the broken link....
Anyway, the gadget does its thing the wrong way around:
- It attaches to the power supply and measures its output voltage and current draw

But in actual fact what is needed is to attach it to the other end of the chain, i.e. connect it to the Pi and then connect the charger cable to the gadget. The reason is that one of the most common problems with Pi supplies is that the cable is too thin and drops a lot of voltage. In such case it does not help reading that the supply itself delivers say 5.05V when the Pi actually only receives 4.61V (happened to me). The missing 0.44V is dropped in the poor cable causing the Pi to run badly. It will run because the core is supplied at 3 or 3.3V so it will be able to boot up. But the networking interface and USB cannot run on too little voltage so they fall off and then you get all kinds of weird errors. Like no connection to the Internet at all...

So the bottom line is that the voltage measurement must be done on the Pi itself or directly on its connector.

[FTrevorGowen]

...
Anyway, the gadget does its thing the wrong way around:
- It attaches to the power supply and measures its output voltage and current draw
But in actual fact what is needed is to attach it to the other end of the chain, i.e. connect it to the Pi and then connect the charger cable to the gadget. The reason is that one of the most common problems with Pi supplies is that the cable is too thin and drops a lot of voltage. In such case it does not help reading that the supply itself delivers say 5.05V when the Pi actually only receives 4.61V (happened to me). The missing 0.44V is dropped in the poor cable causing the Pi to run badly. It will run because the core is supplied at 3 or 3.3V so it will be able to boot up. But the networking interface and USB cannot run on too little voltage so they fall off and then you get all kinds of weird errors. Like no connection to the Internet at all...
So the bottom line is that the voltage measurement must be done on the Pi itself or directly on its connector.

But if your PSU has a separate cable it's relatively easy to measure that cable's resistance with a DMM - those that are really bad are > 0.2 ohm per metre **. Personally I characterise any PSU I own, beg, borrow ... with a simple, dummy load test kit:
http://www.cpmspectrepi.webspace.virgin ... plies.html and
http://www.cpmspectrepi.webspace.virgin ... dPSUs.html
The really good thing about "the gadget" is that it (based on three samples) has good, linear current measurement behaviour:
http://www.cpmspectrepi.webspace.virgin ... octor.html
Trev.
** http://www.cpmspectrepi.webspace.virgin ... esChk.html

[W. H. Heydt]

... http://www.adafruit.com/products/185 ...

http://www.adafruit.com/products/1852

Yeah, I wondered about the broken link....
Anyway, the gadget does its thing the wrong way around:
- It attaches to the power supply and measures its output voltage and current draw

But in actual fact what is needed is to attach it to the other end of the chain, i.e. connect it to the Pi and then connect the charger cable to the gadget. The reason is that one of the most common problems with Pi supplies is that the cable is too thin and drops a lot of voltage. In such case it does not help reading that the supply itself delivers say 5.05V when the Pi actually only receives 4.61V (happened to me). The missing 0.44V is dropped in the poor cable causing the Pi to run badly. It will run because the core is supplied at 3 or 3.3V so it will be able to boot up. But the networking interface and USB cannot run on too little voltage so they fall off and then you get all kinds of weird errors. Like no connection to the Internet at all...

So the bottom line is that the voltage measurement must be done on the Pi itself or directly on its connector.

Sorry about the bad link, and I appreciate that it got corrected.

I agree that I'd like one that did either USB in to microUSB out, or microUSB on both sides (or--ideally--a unit with both connectors on both sides), but it's still a good start as a way to check that the voltage doesn't collapse under load.

[W. H. Heydt]

...
Anyway, the gadget does its thing the wrong way around:
- It attaches to the power supply and measures its output voltage and current draw
But in actual fact what is needed is to attach it to the other end of the chain, i.e. connect it to the Pi and then connect the charger cable to the gadget. The reason is that one of the most common problems with Pi supplies is that the cable is too thin and drops a lot of voltage. In such case it does not help reading that the supply itself delivers say 5.05V when the Pi actually only receives 4.61V (happened to me). The missing 0.44V is dropped in the poor cable causing the Pi to run badly. It will run because the core is supplied at 3 or 3.3V so it will be able to boot up. But the networking interface and USB cannot run on too little voltage so they fall off and then you get all kinds of weird errors. Like no connection to the Internet at all...
So the bottom line is that the voltage measurement must be done on the Pi itself or directly on its connector.

But if your PSU has a separate cable it's relatively easy to measure that cable's resistance with a DMM - those that are really bad are > 0.2 ohm per metre **. Personally I characterise any PSU I own, beg, borrow ... with a simple, dummy load test kit:
http://www.cpmspectrepi.webspace.virgin ... plies.html and
http://www.cpmspectrepi.webspace.virgin ... dPSUs.html
The really good thing about "the gadget" is that it (based on three samples) has good, linear current measurement behaviour:
http://www.cpmspectrepi.webspace.virgin ... octor.html
Trev.
** http://www.cpmspectrepi.webspace.virgin ... esChk.html

Some time ago I suggested to Adafruit that they make and sell something like your test board. I still think it would be a good idea. Mind you, I use Adafruit power supplies for the Model B and have never had power issues with them, but aside from testing what I use (just to be sure), I'd take such a device to Jams to help other people with suspected power issues. I also use cables with 24AWG power wires in them, so I'm not losing much there, either.

Now, of course, it would be good to have a test rig that would load for both ~1A and 2A supplies to check for utility for both B and B+ supplies.

[GTR2Fan]

Is there a dedicated Pi forum where a beginner can go for simple answers to simple questions?

You guys really are your own worst enemies at times. I wouldn't be in the least surprised if some of the noobs coming here to ask simple questions just give up when they see the enormous swathes of totally irrelevant (to their question) bollocks a lot of you type.

Well done you!

[W. H. Heydt]

Is there a dedicated Pi forum where a beginner can go for simple answers to simple questions?

You guys really are your own worst enemies at times. I wouldn't be in the least surprised if some of the noobs coming here to ask simple questions just give up when they see the enormous swathes of totally irrelevant (to their question) bollocks a lot of you type.

Well done you!

Just a bit below this (General) forum on the forum index page, under the heading "Using the Raspberry Pi" is a forum titled "Begiiners". Link: http://www.raspberrypi.org/forums/viewforum.php?f=91

[mahjongg]

Is there a dedicated Pi forum where a beginner can go for simple answers to simple questions?

You guys really are your own worst enemies at times. I wouldn't be in the least surprised if some of the noobs coming here to ask simple questions just give up when they see the enormous swathes of totally irrelevant (to their question) bollocks a lot of you type.

Well done you!

In that case, (while moving the question to "beginners") the answer becomes.

5.35V No!
2.0A Yes.

but providing a little more info than that allows the OP to make his own informed decision.
Also he doesn't have to read on beyond the post that fully answers his question...

But then, as the PI is about learning, it does no harm to do so.
I'm getting a bit fed up with the instant gratification that seems to be required these days.

[Jednorozec]

I'm getting a bit fed up with the instant gratification that seems to be required these days.

I don't want it now, I want it yesterday!

[W. H. Heydt]

I'm getting a bit fed up with the instant gratification that seems to be required these days.

I don't want it now, I want it yesterday!

TARDIS Express...when it absolutely, positively has to be there yesterday.

[joan]

Is there a dedicated Pi forum where a beginner can go for simple answers to simple questions?

You guys really are your own worst enemies at times. I wouldn't be in the least surprised if some of the noobs coming here to ask simple questions just give up when they see the enormous swathes of totally irrelevant (to their question) bollocks a lot of you type.

Well done you!

In that case, (while moving the question to "beginners") the answer becomes.

5.35V No!
2.0A Yes.

but providing a little more info than that allows the OP to make his own informed decision.
Also he doesn't have to read on beyond the post that fully answers his question...

But then, as the PI is about learning, it does no harm to do so.
I'm getting a bit fed up with the instant gratification that seems to be required these days.

Actually the simple and accurate answer to the posed question is Yes and Yes. The Pi can handle the voltage.

However, without the additional information you gave, the OP wouldn't know of the negligible risk to equipment attached to the Pi.