Computer delivering painful electric shock

[Ottonomous]

Hello AT.

I assembled this PC personally, it was my first one but I've never managed to get to the bottom of the shock. It's quite painful and I am afraid it's going to destroy some of the internal components. It's already killed a few flash drives.

I've
- replaced the original PSU
- replaced the PSU power cord multiple times
- ensured the absence of any issues with the home electrical wiring
Yet the issue persists.

I've noticed the shock is mainly present in the upper panel (with the power switch and USB ports) and that the initial symptoms of the problem were USB malfunctions😕.

Also the second area with shock is the rear chassis. The case is a CM 690 II which has been noted to have circuitry issues in the upper panel.

How do I eliminate this issue? 😕

 

[oynaz]

Are you sure that it is not your home electrical wiring? I would start by hauling the rig somewhere else and see if the issue persists.

 

[corkyg]

It could also be the power switch wiring in the case itself. Is the case grounded?

 

[Ketchup]

Unplug the USB front panel from the board first, and check to make sure the board is mounted correctly (all mounting screws with nuts are installed and tight).

 

[Ottonomous]

Thank you for kindly taking the time to respond! I did the following after reading your posts:

Are you sure that it is not your home electrical wiring? I would start by hauling the rig somewhere else and see if the issue persists.

[1] Connected the desktop to my living room tv
[2] Connected it to a voltage regulator and grounded (three-pronged plug) extension cord
[3] Checked the same power outlets using other electronic devices (no static/electrical shock)

It could also be the power switch wiring in the case itself. Is the case grounded?

I replaced the PSU power cord twice for good measure and both power cords are three-pronged. They are both at the specified PSU voltage and wattage.

Unplug the USB front panel from the board first, and check to make sure the board is mounted correctly (all mounting screws with nuts are installed and tight).

[1] Disconnected the I/O connecter of the upper/front panel
[2] Disassembled the PC and ensured all motherboard mounts are in place
[3] Ensured the integrity of all internal wiring
[4] Cleaned the PC and removed as much dust as possible

Unfortunately, the issue still persists. The electrical shock is mainly present in the rear chassis screws and front usb panels.

The only probable diagnosis I believe is the common USB circuitry issue in the CM 690 II cases.:hmm:

 

[C1]

If it were me then I would use a meter to verify first the home outlet used for the computer and then check for any line voltage present between the case areas of concern and the home electrical outlet (eg, white/neutral wire and ground of outlet

 

[Ketchup]

I had the original version and it was a good case. Not to say there couldn't be an issue with yours, I just don't know how that would occur, since you tried disconnecting the top panel USB. Does the bay on the top of the case connect to anything? You may also want to try disconnecting the power switch and powering it on manually.

What power supplies have been in the case?

 

[Flapdrol1337]

[2] Connected it to a voltage regulator

what's that?

Anyway, the best way to connect stuff is to make sure everything is grounded properly. If this is too much of a hassle at least connect everything to the same plug with a box with grounding so there's no voltage difference between the stuff you're connecting. Assuming the equipment doesn't use too much power for one plug of course.

Might also be the weather, if the air is really dry I get shocked when I touch my g25 racing wheel, which then loses it's settings and recalibrates, and I have to restart the game.

 

[Ottonomous]

If it were me then I would use a meter to verify first the home outlet used for the computer and then check for any line voltage present between the case areas of concern and the home electrical outlet (eg, white/neutral wire and ground of outlet

I'll consult an electrician as I don't have any experience with that tool.

What power supplies have been in the case?

Cooler Master Silent Pro Gold (800W) which blew up. Now an 800W Gigabyte Odin.

connect everything to the same plug with a box with grounding so there's no voltage difference between the stuff you're connecting.

I tried this but the problem is still there. I think it's a manufacturing defect in the case...

 

[Ketchup]

I would contact Cooler Master and see if they have any suggestions.

 

[inachu]

When building a pc many times you have to use tiny copper tubes with threads inside called risers. It keeps the motherboard off the case and just grounds it to the case.

Other modern cases have molded risers so you do not have to use the copper risers on the case at all.

Hopefully you are not building a pc with the mother board attached to the case without riser and it needs risers. IF the case does not have molded case risers and you just place the motherboard straight on then there is your problem.

Also sounds like the pc case is a wee bit small for your motherboard.
I had a few server motherboards that managment demanded I make fit no matter what and well those also put out shocks as well.

Tight fitting pc cases is usually not a good idea.

 

[Deders]

Where is the PC located countrywise? Can you be sure that even if your sockets have a 3rd pin for ground, that the ground is actually working as it should. I realise a lot of places were upgraded from 2 to 3 pins in America not too long ago.

I wouldn't have thought it would be USB as they are designed to supply 5v at half an amp, which is nothing. Certainly not enough to be painful.

 

[Ketchup]

When building a pc many times you have to use tiny copper tubes with threads inside called risers. It keeps the motherboard off the case and just grounds it to the case.

Other modern cases have molded risers so you do not have to use the copper risers on the case at all.

Hopefully you are not building a pc with the mother board attached to the case without riser and it needs risers. IF the case does not have molded case risers and you just place the motherboard straight on then there is your problem.

Also sounds like the pc case is a wee bit small for your motherboard.
I had a few server motherboards that managment demanded I make fit no matter what and well those also put out shocks as well.

Tight fitting pc cases is usually not a good idea.

Might want to check data before posting next time. space is not an issue with a 690, and it comes with the appropriate mounting hardware.

 

[inachu]

It could also be the power switch wiring in the case itself. Is the case grounded?

In most cases I would think you gave the correct answer.

 

[inachu]

Might want to check data before posting next time. space is not an issue with a 690, and it comes with the appropriate mounting hardware.

As if everyone has a memory storehouse of what a 690 case looks like but yes if its big then may not be the cause.

 

[inachu]

Where is the PC located countrywise? Can you be sure that even if your sockets have a 3rd pin for ground, that the ground is actually working as it should. I realise a lot of places were upgraded from 2 to 3 pins in America not too long ago.

I wouldn't have thought it would be USB as they are designed to supply 5v at half an amp, which is nothing. Certainly not enough to be painful.

Cheap soloution go to hardware store and buy a $7 recepticle wall outlet tester.

Ground faults suck.

 

[Ketchup]

As if everyone has a memory storehouse of what a 690 case looks like but yes if its big then may not be the cause.

In my case, I do because I have owned one. In other cases, a Google search would lead one to the answer in a few seconds.

From your response, I probably came off as rude, and that was not my intention. Take it has helpful criticism.