Any electricians here? I know my computer is unsafe, but don't know how unsafe

JonJ678

JonJ678

JonJ678

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In short I've done something very stupid and would like to know if there will be particularly terrible consequences. Please avoid spamming this thread with any variants of "you're so stupid" or "you're so cool".

I've put a waterblock on a piece of copper which is unfortunately at mains ac. Between the copper and the waterblock are three layers of pvc electrical tape as I hoped these would isolate the two. Not so, I believe the magnetic field associated with the ac is generating a voltage within the copper base of the waterblock. This voltage is applied to the water in the block, leaving the barbs live.

A length of tubing is connected to each barb, and grounded at the far end. As such I'm fairly confident that any water beyond this short loop is safe (multimeter reports zero, doesn't hurt when I touch them). However my multimeter is no longer reporting sensible values at the psu barbs, set to 600V ac range it's fluctuating between 0 and about 2000. No fuses are blowing while it's operating under these circumstances, so I believe the current running to ground to be small.

How do I go about 1/estimating the risks involved here and 2/isolating the rest of the loop from the psu? Some photos attached.

260ed6f.jpg

2d83wcj.jpg
 
Its late, are you trying to watercool a part of your PSU ?


edit.


2nd pic looks like a ground wire to chassis.

Unless you have opened the psu casing, you have no live voltage outside the psu
 
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Yeah. It all went swimmingly until it turned out the big copper heatsink in a convenient place was live.

Block's on the piece of copper shown here
2598j.jpg
 
:eek:

[very slowly walks away backwards]

Are you doing this because you're PSU is the nosiest part of your PC as mine is, :mad:

Respect for trying though.:cool:
 
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Top tip: Use kapton tape, this will electrically isolate your waterblock while providing good thermal conductivity. :)

Insulation tape is not recommended really, as it also insulates the thing that's getting hot!
 
Kapton tape is probably a winner. Any idea if it'll actually isolate it? I'm pretty certain a single layer of pvc will block 240V, hence the induction theory
 
JonJ678 said:
Kapton tape is probably a winner. Any idea if it'll actually isolate it? I'm pretty certain a single layer of pvc will block 240V, hence the induction theory
Click to expand...
I imagine your readings are from induction, if it's AC voltage going thru the heatsink.

How about putting kapton tape between the semiconductors and the copper heatsink. This way the heatsink can be earthed. :)
 
There's a thought actually. CPU heatsinks are bolted through the board, so probably are earthed. I can run some wires from the barbs on my cpu block to the mounting mechanism as another line to earth.

I couldn't find any data on thermal coefficients of pvc tape but I can't see them being good. I think I'll have to rebuild with kapton tape in the near future.

The block is an xspc chipset one, design is a piece of copper with a lot of parallel slots milled and some acetal to force water through the slots. It looks like it'll be pretty good. It's the largest one I can fit without cutting up the psu itself, which I'm not yet brave enough to attempt. I have no estimate for heat dissipation, I'm hoping for any value greater than zero. I haven't worked out how to measure it, so I'm currently working on "without block, air coming out the psu is hot. With block?" which is woefully imprecise.

Well, it turned on, and nothing has caught fire yet. I'm clinging to induced voltage => earth means no current going to cpu like a drowning man though, not feeling very confident here.
 
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If you can suggest a mechanism by which this leads to harming other people then I'm all ears and will dutifully remove this change. As it stands though the only person likely to suffer electrocution is me, and the only hardware at risk is my own. I appreciate the warning though, and think I will purchase a CO2 fire extinguisher in the near future.

The air coming out of the psu is still hot, so my current suspicion is that the process of electrically isolating the block has indeed thermally isolated it. I'll report back when I get some of the new type of tape.
 
Do other people not come in contact with you in your home or the area near your PC? Pets etc? In the end its up to you mate, i'm a qualified IT tech, Commercial and domestic electrican and also dabble in electronics but i would not undertake this kind of venture.
 
STOP!
Collaborate and LISTEN!
That ain't looking a real good INVENTION
COOLING, the OCUK way
shouldn't be done by a chump OK?
Will he ever stop?
Yo, I don't know,
Turn off the lights,
The PSU might glow
To the extreme I mod a block like a vandal,
And my whole damn rig is a big fat shambles
FARCE!!
 
@Justintime no pets sadly, and no kids, otherwise I'd be much more cautious. It's in a sealed, earthed metal box so there's limits to how dangerous it can be to passers by. There's definitely potential for this to go wrong, but I can't see it hurting anyone. Well, beyond the electric shocks I've already sustained.

@jaybee Well **** you too
 
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JonJ678 said:
@Justintime no pets sadly, and no kids, otherwise I'd be much more cautious. It's in a sealed, earthed metal box so there's limits to how dangerous it can be to passers by. There's definitely potential for this to go wrong, but I can't see it hurting anyone. Well, beyond the electric shocks I've already sustained.

@jaybee Well **** you too
Click to expand...


Sorry for OT but why would you watercool a PSU anyways?
The good ones are so silent you can hardly hear them from 10cm away not to mention inside the case....

I don't think it's any more unsafe than playing around inside your PSU already is but the question that bothers me is that if it's worth the effort at all...

Watercooling the PSU has no effect whatsoever on the system and it's not really going to be any more silent than a quality 140mm fan is.
 
Not something I think I would do, but as far as I am concerned (As a modder, a nerd, call me what you will!) 'becasue I can' is a good reason to do pretty much anything.

It drives my lass wild, 'Why do you have to modify everything?" frequently gets asked.
If it doesn;t do what you want it too, then change iot do it does.
However, watercooliing a PSU is pretty high up on the things I don't think I would do to my PC. Maybe as an excersise in a spare PC, but not my main rig, until it had been tested and running for quite a while.

(You can buy watercooled PSU's by the way!)
 
I know its not as thermally conductive, but you could use an aluminum heatsink- at least then you won't kill yourself! Maybe combine the aluminium HS with a nice quiet 80mm fan and you should be ok.

But still, seriously... WHY??
 
you can indeed buy a watercooled powersupply, for a very high price

Jon is doing this so we don't have to, hell its people like him (and others) that dare to put their engineering skills to the test, this is what got PC modding started anyway, by seeing what is and is not a good idea etc

and we all follow in their footsteps

its called making it your own, like you would your car
 
Gundog48 said:
I know its not as thermally conductive, but you could use an aluminum heatsink- at least then you won't kill yourself! Maybe combine the aluminium HS with a nice quiet 80mm fan and you should be ok.

But still, seriously... WHY??
Click to expand...

:confused:

Aluminium is very electrically conductive . . . . And very thermally conducive . . . .
 
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