Is it normal for some PSUs to have minor current leaks?

[Kanuan]

My friend's PSU unit (Corsair 550W 80 Plus Bronze CX550) has a constant current leak that can be felt by touching its screw holes. To test if the PSU was the sole culprit, I disconnected all its cable from the rest of the computer, removed the PSU from the case and just plugged it alone in the power outlet. As long as it is plugged to the power outlet, touching its screw holes will give a minor, constant shock. 

 

If the PSU is screwed in the case, the screws in the case and some metal parts of the motherboard will also be electrified, even with the PC turned off.

 

His power outlets are NOT grounded, and I know that if the computer was properly grounded the PSU screws wouldn't shock the user, since all current leak would go to the grounding.

 

My main question is: is it somewhat common for non-grounded PSUs to have some current leak, or if any minor current leak should be interpreted as a faulty PSU that should be replaced to prevent damages?

Though having a proper grounded outlet would "fix" the issue, I'd like to know if it is actually the correct procedure of if it would be just "hiding" the issue. From my understanding, grounding is used to protect the user from electrical isolation faults, not to just have normal operation.

 

My own PSU has no current leak, even in a non-grounded outlet. I don't know if this means his one is faulty and mine is working as it should or if having the current leak is not a sign of a fault and just means that my PSU is of higher quality.

Thanks for the assistance! 

[EDIT 1]======

Forgot to mention. He has been using his computer non-grounded normally for some months now, but because we don't know if the current leak is an actual issue or not, we'd to have some clarification on this since his PSU is still under warranty

 

[Elisis]

4 minutes ago, Kanuan said:

His power outlets are NOT grounded

Why?? That's such a safety hazard

5 minutes ago, Kanuan said:

is it somewhat common for non-grounded PSUs to have some current leak

Yes. Case will float if not grounded. 

[seon123]

5 minutes ago, Kanuan said:

is it somewhat common for non-grounded PSUs to have some current leak

Yes. There is a section on it in Aris' newer reviews.

https://www.tomshardware.com/reviews/corsair-rm750x-2021-power-supply-review/2

[SorryBella]

4 minutes ago, Kanuan said:

is it somewhat common for non-grounded PSUs to have some current leak,

very. I have an un grounded power bar hooked up to a grounded outlet that still gonna shock me when the PC is running. Finally got a grounded power bar and ALL of the surge and shocking issue is gone.

[Kanuan]

Oh, you guys are fast. I was planning on sleeping and praying there would be some answer in a few hours. Thanks for the answers!

I had google around forums/reddit and, even though most users said it was normal, no one presented some trustworthy facts to back it up, just the old "trust me on this one".

 

Thanks @seon123 for the link, I'll make a proper test to measure how much current is leaking based on the info there.

 

 

[Kanuan]

7 minutes ago, Elisis said:

Why?? That's such a safety hazard

Basically, his house is really old and doesn't have any grounding whatsover. he do is planning on grounding at least his computer's power outlet, but he doesn't have the money for it right now.

[SorryBella]

2 minutes ago, Kanuan said:

Basically, his house is really old and doesn't have any grounding whatsover.

Im going to guess a brick house? Yeah, those are superbly expensive and there's not many electricians who would work on em, least from where i am

[Kanuan]

Just now, SorryClaire said:

Im going to guess a brick house? Yeah, those are superbly expensive and there's not many electricians who would work on em.

yeah, basically any house here in Brazil. Re-wiring even a small house is not cheap.

[Guest]

12 hours ago, Kanuan said:

My main question is: is it somewhat common for non-grounded PSUs to have some current leak, or if any minor current leak should be interpreted as a faulty PSU that should be replaced to prevent damages?

 

Current leakage for a typical PC power supply is actually 3.5mA.  Enough to give you a good tingle if the PSU isn't grounded and you're barefoot.

 

Medical PSUs can be as low as .5mA, but you have to completely redesign the EMI filtering circuit using very expensive components and nobody in the PC world wants to do that.