Neutral Bonded to Computer Tower

You are absolutly right. Assuming you do have a bond to ground in the receptacle. I have seen dozen of homes where people upgrade the electrical receptacles/switches but do not upgrade thew wiring to include a bond conductor (before 60ish ish there was no ground ).

People (stupid ones) will run a short pigtail to the metal electrical box. Therefore the tower, metal electrical could be energized and nothing would happen bc it wouldn be grounded.

Am i missing something to prevent this?

First: Welcome to CR4.

Second: I think you will find that the most of the people on this site, do have "real life exsperience".

Third: "Am i missing something to prevent this?" No, not really. Except that newer construction has to meet current code, and any retrofit has to meet it as well. But nobody can stop an individual, from wiring up his own home as he sees fit; except the consequences. Mostly those consequences fall on the person doing the work, but sometimes somebody else pays the price. What can I say, it's an imperfect world. That's why those codes were put into place, and why a lot of us (apparently including you) have jobs.

Thank you sir. Thank you for the hosbitality.

And thank god someone has some fresh exsperience. I just get so frustrated with some indiviuals.

I Heard this saying. Do everything as if everyone around you are the most stupid people in the world. I ran a portable toilet company for 4 years and was suggested by the lawyer at one point w.r.t. liability to install signs in the washroom like "Do not drink Toilet Water". "Warning: Water may be Hot". "Turn lock to open". etc.

With that said, viewing this matter that someone brought to my attention. Because they had an electrocution with this. Would it be possible for the manufacturer to be able to create a little relay system that would see that if the tower/neutral is the energized component, it would cut off....

Just a thought.

I'll bet that the people around you feel the same way about you!

Thank you Ace Boeringa. May Allah smile upon you.

"...install signs in the washroom like "Do not drink Toilet Water"."

I just had to laugh! Thanks for reminding me:

Photo now available on the net!

post script: Welcome to the discussion table.

I think Kwoznia understood this quite well in the OP, and Wareagle's explanation and drawing were excellent. For further study, please let me recommend The Soares Book on Grounding and Bonding. It is a bit expensive, but is reputed to be the best reference.

[Polarized plugs, with the neutral blade wider than the "hot" blade, are a step in the right direction, but the 3-wire hot-neutral-ground is better. For those who haven't encountered this, the wiring terminal screws are color-coded yellow (brass) for hot, silver (plated) for neutral, and green for ground.]

All good stuff.

Original wiring in houses let say pre-1960 did not have a grounding wire thus the two pronged receptacle, but it was always supposed to have polarity. The story about "little Johnny" is probably and Urban Myth. Since the usual injury from what you have described did happen, but it usually involved kitchen appliances and water also.

You can see by the above comments that the trade has went to extensive measures to insure injury is damn near impossible. As far as a licensed electrician connecting the cord up wrong, he would be sublject to review and lossing his license or fined. A DIY, well all he has to do is follow the simple written instructions.

I might add that appliances using the two pronged plug, with the large and small prongs. The UL requires the appliance be double insulated to prevent electrial shock.

I would really like to see the article about little Johnny, because something does not make sense in the original post.

Why would the neutral be bonded to the case in the computer tower? I've checked Dell, Acer & HP designs for the US market, and none of them have a bonded neutral inside the box. The grounding conductor (green or bare wire) is bonded to the case, but the neutral is not. Further, All desktop PC's sold in the US should have a 3-prong grounding power cord. The only 2-prong cables for IT equipment supply double-insulated power bricks, with the output side <24 volts.

I believe it is illegal in the US to have either power conductor (hot or neutral) bonded to exposed metal. It would not take improper wiring to cause a fatality. If the neutral conductor broke anywhere between the device and the panel, the voltage of the energized conductor would be found in the neutral conductor from any connected device all the way back to the point of the break. I have seen this occur several times.

There are many ways that idiots can bypass mandated safety designs. Unfortunately, you can't make anything idiot proof, for as soon as you do, the world builds a better idiot.

Kwoznial Quote "I bring this up because when in trade school. We were told and read the article on little Johnny who died when he touched the tower of his new computer tower sitting on thick carpet (non conducting) and pplugged it into a receptacle where the 120V and the neutral were reversed."

I too have a problem with this story. if Johnny was sitting on a non conducting surface he would not have been injured. I do know of a true story that may hit home. There was a young boy who was electrocuted at the beach. He had just got out of the water an wanted a Coke. When he reached into the machine he received a shock and died. The investigation found that the coke machine was powered by a 2 conductor cord and was mounted on rubber stand offs. The energized conductor was making contact with the frame but because of the rubber mounts, it was insulated and the breaker did not trip. The boy was wet and standing on a concrete pad when he received the shock. The installation was old and was not up to the the current code. If it had been updated it would have had a GFIC receptacle and it would have tripped saving the boys life.

I agree completely with the last two posts. If there is any truth to this tale, that truth is more then likely one of an over jealous instructor making up a less then truthful story as part of a lesson (if this is what prompted this story, the teacher needs to go back to teacher school), or, a teacher hoping someone would call him on it. Lets hope the latter case is true and not the former one.

If for some reason the neutral was in fact bonded to the case and the hot and neutral were flipped at the receptacle, the breaker feeding the circuit should have tripped instantly when the "3 prong" plug of the PC was plugged into the receptacle.

Why? Because the "bond", or "equipment grounding conductor" as our friends to the south call it, is tied to the case. Or, was the teacher claiming the bond was not present also? Or, had the bond pin on the 3 wire cap been hacked off? In any case... Pretty flimsy.