[SOLVED] Current in chassis from motherboard

Apr 13, 2019
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Every time I plug any power supply cord from PSU to motherboard, I feel a sharp tingling in all over the chassis even without powering on the PSU button. Oddly, the voltage tester screwdriver isn't recognising any current. What could be the reason behind it? How to mitigate it?
 

DMAN999

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Apr 17, 2019
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It sounds like your motherboard is touching the case which will short it out which will certainly damage it.
I would check and make SURE you have all the motherboard standoffs are installed and that the motherboard isn't making contact with the case anywhere.
If that isn't the issue I would try a different PSU and see if that resolve the issue.
 
Every time I plug any power supply cord from PSU to motherboard, I feel a sharp tingling in all over the chassis even without powering on the PSU button. Oddly, the voltage tester screwdriver isn't recognising any current. What could be the reason behind it? How to mitigate it?
That is typical of an ungrounded case. Double check the power cable from your power supply to the power outlet and make sure it has all three contacts in use. Make sure it is fully inserted on both ends and do not use a three-wire to two-wire adapter.

Use a power outlet circuit tester like this:

https://www.amazon.com/Tripp-3-LED-CIRCUIT-TESTER-CT120/dp/B00025ALCA

To check the outlet to make sure all wires (hot, neutral and safety ground) are properly connected.
 
Reactions: DMAN999
Apr 13, 2019
42
2
45
1
That is typical of an ungrounded case. Double check the power cable from your power supply to the power outlet and make sure it has all three contacts in use. Make sure it is fully inserted on both ends and do not use a three-wire to two-wire adapter.

Use a power outlet circuit tester like this:

https://www.amazon.com/Tripp-3-LED-CIRCUIT-TESTER-CT120/dp/B00025ALCA

To check the outlet to make sure all wires (hot, neutral and safety ground) are properly connected.
I have isolated the PSU and I'm using a grounded outlet (just had an electrician over and got the outlets tested for ground). Even when nothing is connected to PSU, I'm getting the sensations from the screws which fixes the PSU in the case.
 

DMAN999

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Apr 17, 2019
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I have isolated the PSU and I'm using a grounded outlet (just had an electrician over and got the outlets tested for ground). Even when nothing is connected to PSU, I'm getting the sensations from the screws which fixes the PSU in the case.
That sounds like the PSU is bad and somehow shorting to the case.
If that PSU is new I would return it.
I'd also make sure you get a Quality PSU and not some cheap off brand PSU.
 
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I have isolated the PSU and I'm using a grounded outlet (just had an electrician over and got the outlets tested for ground). Even when nothing is connected to PSU, I'm getting the sensations from the screws which fixes the PSU in the case.
I'm not sure what you mean by 'isolated' the PSU. The PSU case must be in electrical contact with the computer case. If you have good three-wire cable connecting the PSU to the outlet-- which you're positive is good-- then your PSU is bad as it's not grounding the case to the safety ground wire.

What PSU do you have?
 
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I'm not sure what you mean by 'isolated' the PSU. The PSU case must be in electrical contact with the computer case. If you have good three-wire cable connecting the PSU to the outlet-- which you're positive is good-- then your PSU is bad as it's not grounding the case to the safety ground wire.

What PSU do you have?
Seasonic s12ii 520w

By isolated, I mean I've taken out the PSU from case and on touching it after connecting it to the power supply is giving me current shock.
I'm 100% positive the PSU is faulty and I'll have it replaced as it's new
 
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Seasonic s12ii 520w

By isolated, I mean I've taken out the PSU from case and on touching it after connecting it to the power supply is giving me current shock.
I'm 100% positive the PSU is faulty and I'll have it replaced as it's new
It may not be the reason for this since you're electrically isolated the PSU case from the PC chassis. But it could have a ground lead that's come disconnected from it's chassis too. If it does, then the entire system is left to 'float' at whatever potential it wants and that's what causes the tingley feeling.

As a simple test you could connect a wire from the PC case to the screw that holds the plastic cover on the outlet, which is ground if the outlet is properly wired. If the tingling goes away then it's either the PSU or the three-wire cable from PSU to outlet that's faulty.
 

ex_bubblehead

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It may not be the reason for this since you're electrically isolated the PSU case from the PC chassis. But it could have a ground lead that's come disconnected from it's chassis too. If it does, then the entire system is left to 'float' at whatever potential it wants and that's what causes the tingley feeling.

As a simple test you could connect a wire from the PC case to the screw that holds the plastic cover on the outlet, which is ground if the outlet is properly wired. If the tingling goes away then it's either the PSU or the three-wire cable from PSU to outlet that's faulty.
This is a safety issue and not even close to being something you want to play with. It's been stated that the outlets have been checked and verified to be correctly wired. Just replace the power supply AND line cord and be done with it. Anything else is literally playing russian roulette.
 
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Well I played the Russian roulette: Connected a separate wire to the PSU and connected it to ground; plugged in the PSU with its cable. I didn't feel any tingling. I even connected the PSU with another power cable and still felt the tingling.
 

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