Exactly as stated in the title. All my life I’ve been able to touch my phone or computer’s electrical charger output (accidentally or for whatever the reason) with no sort of “buzz” or feeling from the electricity going through the output. At least that has always been my experience with it.
Just in case: Don’t intentionally try this of course.
In: 64
Electricity can only flow through something, like your finger, if you are touching both the negative and positive poles at the same time. Charge receptacles and adapters are designed so that its only possible to touch either the positive or negative side. Ones on the outside, and the other on the inside where its typically impossible to touch while also touching the outside
USB and many other kinds of charger plugs are designed so the outer sheath of the plug is the ground connection, which is always safe to touch. The actual conducting pins are inside the sheath and very hard to access except by the corresponding socket.
So phones are charged at 5V and between 1~2 A at Direct Current.
Most households received current at 120/240V, 200A at Alternative current.
So the difference is like between taking a 5cm high stream of water in the face at 1-2 km/h
And
Taking alternating 2m tall waves from the left and right, at 200km/h.
You won’t even feel the first one in your sleep, but the second **will** kill you.
As what the other comment said, most chargers do not have the power pins where you can touch them, most of the time the neutral/ground is on the outside and the voltage is on the inside, at least when talking about barrel plugs. As for the ones you can touch the voltage pins (think Apple lightning) the voltage (usually only 5v or maybe 12v) isn’t enough to pass much current through the resistance your skin. If you put it on your tongue, you might feel something, although I wouldn’t recommend it.
What you actually feel is current, which is Voltage divided by resistance. Your bodies resistance is pretty much fixed (for skin, if you use your tongue or something it will be lower) so as the voltage goes up, the more current you will have going through you.
Additionally, AC and DC current do behave differently, but that is relatively minor compared to the fact that AC (the power in your home) is usually on the order of 120v or 240v, whereas the highest common DC voltages for chargers and things are 24v, which is barely enough to feel if your hands are sweaty and you touch both terminals.
Because chargers have a transformer that lowers the voltage from the full voltage of the main circuit in the wall. That’s what’s in the little block that you plug in. Even if you were able to touch + and – contacts, that would put 5 Volts across your skin for a phone charger or ~20 Volts for a laptop charger. For comparison, the wall circuit is 120V in North America and 220V in Europe. Charging a phone or computer with that much direct power would fry all the tiny components, so the chargers have a transformer that reduces the voltage.
There is a printed industry standard somewhere that says the limit to how many volts can penetrate dry human skin is “somewhere around” 60V, whether it is AC or DC.
If you touch 72V and it doesn’t shock you, there are also many variables. I don’t know of anyone who can’t feel 120V AC.
the more volts you have, the fewer amps you will need to achieve “X” amount of power. This is why 48V is popular for off-grid systems. You can series solar panels to output 120V DC to charge a 120V battery, however, a fully charged 48V battery is around 54V, and stacking one more 12V battery onto it would make it around 65V, plus or minus. The nominal 12V lead-acid batteries are around 13+ volts when full, and around 11V when they are considered depleted.
Lithium cells are only 4-ish volts each, so a 52V ebike battery (14S) is around 58V when fully charged, and going to one more cell in series makes that roughly 62V.
If you want to use mass-produced components to save money, the next big jump is up to 72V (20 lithium cells in series).
You should always exercise caution around high-powered batteries, even just a 12V one.
In addition to what others have said, it’s also good to note that even if you did touch the wires and get shocked you have to consider that the two wires would touch you very close to each other.
if you touch two wires, one with each hand, the electricity flows through your body and probably across the heart, not good.
if you touch two wires with one finger or one hand then the electricity flows through just that party of your body and causes less damage… possibly no noticeable damage if the power is low
I had the experience of taking a desktop to Africa (240V) and getting a buzz from usb cords. The power supply could be switch from 120V to 240V, but touching the usb cords could give you a little shock, which usually never happens.
Electricity needs a certain amount of power to push through your body. Your house plugs have lots of power and can push through your body. The end that connects to your phone has less and can’t push through the same way
It’s really simple. Dry dead skin, like the outer layer of skin, has a high resistance to electricity. There is simply not enough voltage to overcome the resistance. You phone charger is outputting between 5v and 12v, and a few amps. A fee milliamps is enough to stop your hear, but the voltage has to be high enough to overcome the resistance. A car battery has hundreds of amps, maybe 600 to 800 amps. But the 12volts isn’t enough to overcome the skin’s resistance so you don’t get a shock from it.
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