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New 2017 Macbook Pro 15 Inch giving me static electric shock. Is it normal?
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Ian.M:
From the PDF of the IEC 60950-1 standard I linked in reply#34

--- Quote from:  IEC 60950-1 Section 5.14 ---For an accessible non-conductive part, the test is made to metal foil having dimensions of 100 mm by 200 mm in contact with the part. If the area of the foil is smaller than the surface under test, the foil is moved so as to test all parts of the surface. Where adhesive metal foil is used, the adhesive shall be conductive. Precautions are taken to prevent the metal foil from affecting the heat dissipation of the equipment.
--- End quote ---
So, to get a repeatable and reproducible measurement, if you cant get good metal to metal contact between the D.U.T and your probe, cut a strip of Aluminum foil of those dimensions,  take some hookup wire, strip the end, fan the strands and tape it to the middle of the foil for a convenient connection point, and push the foil (wire side up) against the surface of the D.U.T. using something soft and insulating.  e.g a sealed plastic bag full of air,  a dry soft sponge in a plastic bag or a balloon.  Also, record the mains voltage when you perform the test.
ciccio:
Years ago I had a similar problem with a Toshiba laptop.
I was using it to control a loudspeaker processor via the RS232 interface, an when the laptop was mains powered, via a brick with a two-prong plug, I got a noisy ground that resulted in a lot of TX-RX errors (it also lighted the neon on my test screwdriver) 
A quick solution was an isolation transformer connecting the mains socket to the power brick (with no earth wire).
(The controller was mains powered, but it's earth came from a socket located at about 50 meters from me and the circuit ground was connected to earth via  100R//100nF, as was usual in audio equipment in these years)
 Best regards
Vtile:

--- Quote from: Ian.M on August 31, 2017, 07:59:00 pm ---... snip .. PDF ...

--- End quote ---
This foil method is almost same as (were?) used to measure the conductivity of electrical laboratory surfaces, IIRC it were from some (old) standard, but can't again recal if it were national or international. The method did came to me as 2nd hand knowledge, but from trustworth oral source.

Thanks for the post, writing that to my notebook.

PS. Does the IEC 60950-1 mention anything about current shunt resistor in this case? I just noticed the link...
bd139:

--- Quote from: electrolust on August 31, 2017, 05:25:07 pm ---
--- Quote from: bd139 on August 31, 2017, 09:52:49 am ---Just measured current between my ThinkPad T440 and ground: 82uA.

And the MacBook again: 103uA

--- End quote ---

I thought T-series were all plastic bodied?  Mind saying where exactly you measured on the case?  Can you feel the 103uA 0.103mA?

You inspired me.  I have a new USB-C MB from work, charging with Apple 2 prong adapter, and the current between case and ground is ... unmeasurable.  Am I doing it right?  I'm using the uA DC range, hot lead touching the MB case and ground lead touching the metal of a wrist static band that plugs into a wall outlet ground plug.  On the ACV setting I do measure 110V between hot and the the wrist band (ground plug), so for sure the ground wire is connected in the outlet.

From what I can gather, there should definitely be SOME leakage current, so I must be measuring it incorrectly?  Or is it possible that my charger doesn't in fact leak.

--- End quote ---

T series is plastic bodied although the ports have metal contacts. In this case I plugged a metal USB stick in and measured from that as it's connected to the inner frame.
pedro380085:
IF we replace the charger, the problem should go away? Or the macbook pro unit is also damaged and needs repairing?
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