Feeling electric current on MacBook Pro M1 with charger plugged in

Apple stopped including the Grounded AC power "extension cord", probably as a cost saving.

it is available at the Apple Store for US$20.

I have a diagram of the "full Kit"

(for Readers who do not know the small head is replaceable with the extension cord)

.

These are US cords, UK is similar but a bit larger.

The "tingly" sensation of touching the case of the MacBook is totally normal.

Please note, it is uncomfortable, but not dangerous.

As the power supply is double isolated and the ground of the power supply (the power return wire) is connected to the chassis - it is inevitable that some parasitic voltage will appear on the chassis at around half the supply voltage (60V USA, 120V UK, 110V EUR) - this is the reason why many commenters here don't notice it - they are US/Canada users.

If you look at how a switched mode power supply works, you'll see a there is a essentially a high frequency switch driving a transformer (transformer efficiency varies with frequency and size) and this causes a lot of interference, to get rid of this interference a filter (a capacitor) is connected to "ground" to remove it. However, with a double insulated device, there is no actual "ground" so the chassis has this parasitic voltage sitting on it, the current is microamperes, hence not dangerous.

So, yes, it is very annoying but it is easy to solve, buy an Apple extension cord, it has the ground pin connected and solves the problem entirely. I would dearly like to know why the ground pin isn't connected on the supplied adapter?

All you need as a work around is the 3-conductor "extension cord" for your power adapter, US$20. This allows the power adapter to ground internally, and then you will not fell the tingling.

I recommend you NOT hold your breath waiting for a recall, or fight with Apple Genius Bar about whether and how these Macs and power adapters may or may not be defective, but work on getting yourself comfortable in the short run.

...

I believe a little lesson in electro-magnetism is due...

YOU DO NOT NEED A NEUTRAL WIRE from the charging block to the MacBook case for the ghost Voltage to dissipate, let alone a strong one. Electric energy is NOT transmitted via the electrons in a wire, but via electro-magnetic fields produced by electrons moving in the wire. The energy is actually transmitted via photons that travers through the electro magnetic fields surrounding the wires. But let's not go into quantum physics here.

More important is that the grounding of metal surface in electronic devices is not necessarily required, what is required is the grounding of the electronic parts producing a strong magnetic field, and that would be the charging block.

In essence, when you ground the charging block the energy caused by the electric field of the block is dissipated into the ground, similar to a lightning rod that directs the energy of a lightning bolt into the ground. If you do not have a grounding of the charging block, the energy of the electric field must go somewhere. And it does! It traverses via the electromagnetic fields surrounding the wires and ends up as ghost or phantom Voltage on the MacBook case.

And as we are in Europe, the charging block converts 240V, which leads to a ghost or phantom Voltage of about half that value (110-120V). Even at low amps, this is a pretty unpleasant Voltage.

Sorry, but you are wrong.

I've sent my intel macbook pro in for service *twice*. I've tried *3* different charger blocks they *all* exhibit the same behavior with 2 prong that goes away when using a grounded 3 prong cable. *3*, so no I don't buy that all the charger blocks are broken the same way.

You do understand the problem right? W/o a true ground, and when neutral has a charge on it due to less than perfectly clean power (common) the case takes on a charge based on that. This isn't something broken that can be fixed by service, it's a design issue of having the metal case be attached to the logic board ground, and then not having a true ground.

You keep mentioning buying a 3 prong adapter and I don't know why since I said that's the fix. The problem is apple moving *away* from it. Anyway I'm done responding to this thread this is going in circles at this point.

I can confirm i have this problem too. im in Kenya, we use 240v. I have tested this with 4 macbooks in our possesion (2012 mbp, 2013 retina mbp, 2020 m1 macbook air, 2021 m1 pro macbook pro ) of course that means using different chargers given the different generations of the computers.

when we use the cable, NONE of the macbooks experience the issue, when we use the duckhead, ALL the macbooks body have the tingly touch feeling.

Iv seen a user here saying that its a faulty charger or macbook, BUT from my test all these macbooks with their different chargers cannot be faulty, otherwise why is a grounded cable solving the issue on all of them?? clearly this is an issue experienced by those in 240v countries so if you are in north america, please admit you may never experienced this issue so your experience may be limited.

The MacBook itself is connected to the Power adapter with a cord that contains exactly TWO wires, One is up to 20 Volts Power, and the second is Return for that power. NOTHING More.

LOW voltage appliances are not required to have an earth ground, and they do not have their chassis Earth Grounded -- the chassis may be used as a conductor, just as it is in a 12 Volt automobile or truck.

The power adapter may, in error, allow leakage of a tiny amount of AC power, possibly perceptible. This is NOT intended. If you connect an AC power cable cable with earth ground, the power adapter can operate correctly, even if the Power adapter has that minor internal error.

Sporadic reports of this issue are seen here from both 240 Volts and 120 volts Users.

"Parasitic currents picked up from the air" - total nonsense.

The tingling is coming from the parasitic high frequency leakage in the power supply, look up "Y safety capacitors and EMI" you'll then see the switching transformer outputs are connected to the chassis via a pair of Y capacitors, tiny values, in the order of a couple of nanofarads, enough for a decent tingle, no more. Adding a ground/earth to the "duck head" would contravene the double isolation standard for the power supply. The unfortunate problem of this decision is anything that is plugged into the MacBook that also has a "floating" power supply, will present that voltage (along with the MacBook's PSU) onto the chassis. For now, I expect anyone who notices the "tingle" to have either delved into fantasies or bought a $20 extension cable...

I will just add here that i got a brand new macbook pro last week and i plugged it in and it was `electrified` as well. My husband does not feel it but it made my wrist ache for days just after touching it less than a minute. Apple said they will replace it. I already did my research, but after i organised it with apple. So after the return process was done, i ordered the extension cable because I had a feeling that the new one will come and then when i need to charge the laptop i wont be able to use it otherwise i will be in pain. SO, today the apple mouse arrived. I plugged it in to charge in an adapter and the aluminium bottom of the mouse did the exact same thing. I plugged the cord then into my other laptop and it stopped givng the sensation. So I fully expect the new mac to do the same. And NO, there is no wiring problems in the building as it happens in different places. In my house, in a shop in town, at a friends house. It is indeed just the apple design issue... Idk why not fix it but ok.... The laptop better last for that price tho..

And if you are in the EU, no matter where you bought the product, you have 2 years guaranty/warranty, and either Apple or the reseller must repair, replace or refund. Having said this, if Apple refuses, one must likely prove that Apple is at fault in this case.

<<. Who ships a computer that by default electrically shocks the user >>

Nobody, INCLUDING Apple, Inc.

Your sample of power adapter is defective.

You need service to correct the underlying issues, or if no longer under warranty, upgrade to a slightly larger power adapter that has a replaceable AC power cord. The ones with exactly the same DC connectors {MagSafe-1, MagSafe-2, MagSafe-3} are widely interchangeable across all models of Macs as long as you don't try to use one smaller than the original.

I am also experiencing this issue with a newly purchased M2 MacBook.

I feel the electrical sensation when trying the following:

• Using the supplied mag safe cable and supplied two prong wall power adapter.
• Tried different wall power outlets using the supplied power adapter.
• Tried a non-Apple two prong wall power adapter used to charge my iPhone.
• Tried connecting USBC to USBC, from the provided adapter to the MAC.
• Touched 3x MacBook at a local authorised repair store, 2x Pro and 1x Air, and all had the same issue.

I do not feel the electrical sensation when trying the following:

• Connecting the MAC via USBC to USBC, via a DELL docking station with power delivery.
• Connecting the MAC via USBC to USBC, via a DELL monitor with hub with power delivery.
• Connecting the MAC via Mag Safe cable with the USBC end connected to a dell docking station.
• When disconnected.

I have been told this is normal, and expected, and is safe but no one wants to put that in writing. I am also being told that the 3x prong adapter cable extension may fix the issue.

Found this when searching YouTube:

MacBook electric shock leakage issue when charging

https://www.youtube.com/watch?v=q7LIBftSAfk

Is this really safe? What if someone has a heart condition, or pacemaker?

Is electrical issue normal/expected?

if you bought DIRECT from Apple, not through a Reseller of any description, you have 14 days to return your purchases for replacement or full value refund (your choice) for any reason.

If you bought through a Reseller, they are free to set their own prices and their own policies.

Exactly my point. And the charging block is NOT GROUNDED !!! But the situation is not equal everywhere, because in the US the Voltage is 110V whereas in Europe it is 240V. The strength of the electric field depends in the difference between input and output voltage. 240-28V is more than double 110-28V. Hence the electric field produced by the charging block in Europe is stronger and in a none grounded situation causes more leaked Voltage than in the US. So US and Canadian owners might not feel the effect that much.