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rogthewookiee
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Help my computer shocked me!

Sat May 13, 2017 3:37 am

I managed to convince my company to ship my computer to me ( I live in Liberia). It arrived and it looked like it had made it without any abuse.

However, I discovered that I couldn't get to one of my HDD so I opened up the back panel to get to the drive cages and found chaos. The case is a Fractal Design Mini C so you can't see the drive bays from the motherboard side.

The internal drive cage had been bent so the HDs were in a pile on the bottom and the top half of the SATA cable had sapped off and was stuck in the drive and the other end hanging free. As I tried to extract the HDs from this mess I got zapped! I pulled the plug from the power supply, but as I tried to turn off the PSU switch I got an even bigger shock. I continued to get shocked as I tried to move the drives.

The computer was properly declared and insured, so I just need to figure out what to do and make a claim. Any ideas?

My current theory is it got dropped really hard, which was enough for the weight of the HDD to bend the cage and snap the cable. I don't think it is a stretch to think that some of the internal components on the PSU are now similarly damaged. I tried to plug in the other HD to the working SATA cable to see if the drive was OK, but got shocked so I gave up for now.

Would it be enough to just replace the case, PSU and SATA cable? I'm tempted to also include the cost of the HD since i'm not sure if it works yet.
 
just brew it!
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Re: Help my computer shocked me!

Sat May 13, 2017 7:14 am

Are your electrical outlets 2-wire or 3-wire there? The shocks may be due to a badly wired outlet.

I would be surprised if all of the hard drives survived without damage if the case was dropped hard enough to bend the drive cage.
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meerkt
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Re: Help my computer shocked me!

Sat May 13, 2017 7:57 am

If the data on the HDDs is important I'd remove them from the computer and use a sacrificial HDD when reconstructing and testing the PC.
Only when everything seems okay I'd put the original HDDs back in.

For the insurance claim, did you take photos the first time you opened it up?
 
TwoEars
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Re: Help my computer shocked me!

Sat May 13, 2017 8:24 am

If you've got a power problem all roads lead to the PSU. Be very careful now! You could die from this stuff. Even with the power cord out the capacitors hold a pretty nasty charge. If the case has been dropped and the PSU is shorted to something all bets are off.

Also - as a golden rule you should never work inside a PC unless the power cord is unplugged.
 
rogthewookiee
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Re: Help my computer shocked me!

Sat May 13, 2017 11:01 am

I've taken everything apart now and I don't see any other signs of damage. I didn't open up the PSU, but nothing looks badly wrong.

The outlets are two wire... i've not seen a single residential home with three wires. We've rewired all of our work sites at great expense (since we are running million dollar lab equipment). In my parents house (cira 1950) there were no ground wires prior to the rewire. The computers worked without shocking you there!

By a badly wired outlet do you mean having a hot neutral. If that was the case wouldn't it have exploded already? Maybe the neutral and the hot are switched in the outlet?

Any suggestions for isolating the PSU other than plugging it in and seeing if I get shocked? (it is outside the case now)

I started taking pictures when I noticed something wrong. I have all the original packing material though.
 
synthtel2
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Re: Help my computer shocked me!

Sat May 13, 2017 1:11 pm

Am I understanding right that it continued shocking you after you had unplugged it from the wall? If so, the PSU is definitely toast, probably dangerous, and I would make no further effort to debug that if I were you.

If that's what's going on, the energy for it is most likely coming from the APFC cap, which needs to store enough energy to cover the PSU's rated output (550W?) for something less than 1/120th of a second. It usually does this at something like 400V. This capacitor can kill you. I've cracked open PSUs before (which people will rightly advise against, and nobody should do unless they're very sure they know what they're doing), but I wouldn't want anything to do with one that's doing what you describe. That cap obviously isn't directly shorted anywhere, but if power from it is following an unknown and unintended path at voltages you can feel, something is broken enough to be scary.

If I were in this situation (and am understanding the situation right), I would handle this PSU with one hand only (so if it does give you a bigger zap it won't go to your heart), set it somewhere out of the way for a few days (or however long you feel is appropriate) to try to make sure it's discharged, then throw it away. I would definitely NOT ever plug it back into the wall.

Edit for one other theory - it could theoretically be coming in through an ethernet cable or something. I'm not familiar enough with that to say much more on it.

Either way, if you were getting repeatedly zapped when messing with hard drives, the problem has probably toasted a lot of other components by now. :(
 
The Egg
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Re: Help my computer shocked me!

Sat May 13, 2017 1:49 pm

Yeah, there's something seriously wrong there. My suggestion is to put on some heavy gloves, carefully put the computer back into it's original packaging, and then do whatever you can to get your money back.
 
NovusBogus
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Re: Help my computer shocked me!

Sat May 13, 2017 3:15 pm

This all sounds very, very bad. I think you have some broken/leaking components and shorts in addition to bent hardware and likely totally destroyed hard drives.

Since it's insured I wouldn't bother with any kind of component replacement, just send the whole thing back. If it's unplugged now it should be good to go--make sure whoever you send it to (insurance company? manufacturer? your employer?) is aware of what it's doing so they treat it appropriately.
 
rogthewookiee
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Re: Help my computer shocked me!

Mon May 15, 2017 12:54 pm

Thanks everyone. Safely back in box waiting to hear back about the damage claim....

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