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This is a question of safety for children using the device while they are still being shipped without a case.

The USB power source is expected to provide 5V and at least 700mA. Is this enough to give a shock?

Do any components on the board step the voltage up, giving a higher voltage?

Capacitors certainly would have the capability of giving a sudden release of current that is briefly higher than the input current (I remember reading a few accounts of people being shocked by a standard PC after unplugging it, thanks to the capacitors in the PSU). Would this be a possibility too?

I guess what it comes down to is how safe a Raspberry Pi is for a child to be using, if it doesn't have a case.

Maria Zverina
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Highly Irregular
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    Even if it is safe for children to touch, it may not be safe for the device itself. –  Jun 13 '12 at 06:22
  • I'd take that "may not" and take it further to "definitely isn't". But not much in a house is completely safe from young children anyway! – Highly Irregular Jun 13 '12 at 06:25
  • I feel sorry for the device. Without any experience, I doubt any shock is going to really hurt and it will probably just teach them not to touch raw PCBs whilst powered. – Alex Chamberlain Jun 13 '12 at 07:40
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    I've touched my device all over while powered on (I'm a careless idiot) and so far no shocks and no damage. – Jivings Jun 13 '12 at 09:11
  • It is a circuit board... the edges, yes, the components, maybe, the leads? no – Sam Sussman Jun 13 '12 at 12:40
  • My father always said, volts jolt, amps kill. Since the RaPi is 700mA at 5v there's very little real energy there, to step up the voltage substantially you would have to step down the current substantially too, and even honking big capacitors at low voltages are unlikely to give more of a shock than shorting PP3 battery terminals with your tongue. *8') – Mark Booth Jun 13 '12 at 14:08
  • Flash memory cells are erased using high voltage right? –  Jun 13 '12 at 14:13
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    @Tibor Highvoltage can be 5V0 in a 3V3 driven IC. Hence high voltage. It does not mean 660Volts. To the OP- Computer PSU capiitors will never shock you - unless you open the PSU up and stick you fingers in there. Thats why it sold with a case and a sticker that says do not open or you will die. The Pi has no need to because it is safe.. unless swallowed. – Piotr Kula Oct 19 '12 at 14:43
  • You can get a shock from the grounded case of any device (even powered off) if you are also in contact with another, different, ground. Which is more common than you might think, especially in a lab setting. – Alistair Buxton Oct 19 '12 at 20:28
  • Will touching to Pi while on damage it ? – Suici Doga Jun 13 '16 at 05:29
  • @SuiciDoga You're best to ask that as a separate question if you want an answer! – Highly Irregular Jun 13 '16 at 08:48

8 Answers8

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Since everything on the board is 5V and below you would need to have a very low skin resistance to even transfer enough energy to cause any interference on the board let alone shock you in any way.

You might not want to try to licking it, but touching shouldn't be a problem. You generally don't get a shock even from 9V and 12V batteries (unless licking is involved).

Mark Booth
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bardiir
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I'm going to be bold and just say no!

While it's true some big capacitors can retain their charge and shock you, there's none nearly big enough on the Pi for this to happen, and I don't believe there's anything on the Pi that runs much above 5V anyway. Definitely not at a voltage that could shock you!

berry120
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There's only low voltages on the Raspberry Pi as others have said.

You do need to be careful not to give your Raspberry Pi a shock though - static discharge that you don't feel can be enough to kill it.

Martin Thompson
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For those who said it's not possible to receive a shock off the Raspberry Pi - you are wrong. I got quite a nasty jolt from the capacitor next to the micro-USB power input. The device was unplugged at the time. This was a concern as I have a pacemaker fitted, but fortunately the charge is nowhere near enough to cause any problems there.

The Pi still functioned after with no noticeable issues. Perhaps different individual boards are more susceptible to delivering shocks than others.

Mequa
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  • It might be helpful to describe "nasty" in a little more detail. Presumably you touched it with your finger; was it strong enough to make your muscles contract substantially? – Highly Irregular Oct 19 '12 at 09:42
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    It was enough to feel like an insect bite or sting. Still medically harmless for most people though, and in my case the R. Pi still functions fine. – Mequa Oct 21 '12 at 01:45
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Is it possible? Probably. It is an electronic device and problems can happen, especially if you are mucking around with the GPIO. However it should never happen and I would be shocked to hear of it. The purpose of the raspberry pi is to be child friendly!

Shane Hudson
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An improperly isolated power adapter driving Raspberry Pi can cause electrical shock.

Usually most power adapter usually used to drive Pi are SMPS. Below is a picture of proper SMPS isolation:

enter image description here

You can see a large slot on the PCB (below text L-4765) that provides electrical and physical isolation between the primary and secondary sides of the power supply. No tracks or electrical connections are routed across the slot.

New cheap manufacturers can cut corners and don't adhere to standards and hence may not isolate the primary and secondary sides properly. The primary side is connected to Live AC voltages.

Here is an article that has more details.

Wikipedia article on SMPS - Search for "shock"

Power supply isolation article by Sunpower

Chetan Bhargava
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0

My daughter got a tingle from the audio output on her Pi. I tested it with a meter and it was only 5V so I'm surprised she could feel it, but she did.

Tim de F
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It's probably more dangerous to prick or cut a finger somewhere on the Pi than to get a hazardous electrical shock. But you might get a jolt anyway, if you are statically charged, for example by a carpet, this energy might flow over the grounded shielding of the USB- or network socket, if you touch it, sparkling, but doing no harm to you or the device. This might be mistaken as getting a jolt by the Pi's electrical system.

Balin
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