shock from switch plate

[onlyinamerica]

hi. Just finishing up building a new house and yesterday they just put in new rugs. Funny thing is that as I walked across the floor and shut off one of the three way switches that I got a shock. I'm thinking I built up some static E and discharged on the screw. Is this supposed to be that way or do I have a problem with the grounding?

My 200A service goes: panel, main disconnect, 50 feet to main panel with subpanel. Grounds and neutrals all separate and then tied together at the disconnect. #6 for ground wire out to well casing.

:shock: Thanks
Dan

 

[charlie b]

Those of us who have felt both a static electrical discharge and a 120 volt shock will state that (1) Neither is pleasant, and (2) They are nothing alike in the way they feel. The static is sudden and over as soon as it starts. It is felt only at the point of contact (e.g., tip of your finger). The 120 volt shock is felt in the muscles of your hand and arm (and perhaps other places), and the unpleasant feeling remains with you for a few seconds after you let go. It is like the difference between being bumped by another pedestrian in a crowed street and being knocked down with four other people landing on top of you.

So, which of these describes the shock you felt?

My money is on the static electrical discharge.

 

[onlyinamerica]

oh, it's ESD I'm sure. Sadly we're all familiar with both. The low humidity surely aids in the breakdown. Since the plates are that, ahem, "unbreakable nylon" I don't have concerns about needing the screws to be metal since the switches are grounded individually. I would gather I could get the nylon screws to prevent this discharge. Then I could discharge that ESD onto something better, my wife!!! :lol:

 

[peteo]

Sorry, there's no little emoticon for 'cringe.' Once I write this, you'll see why I wanted to use it.

The type of carpet will greatly influence buildup of static charge. It is possible to pick a paper up off a desk and build up enough charge to damage something sensitive. If you can see a spark, you're above 2000 volts.

Now for the cringe part. To quote someone more familiar with this forum than I am, better get my umbrella! A boss who worked in an air force base in Arizona said that they would have sparks an inch long, and he told me their solution. (They would shake a couple suppositories in water and spray the rug with it.) A DI once told me that he had seen huge sparks from helicopters, but I don't know this to be a fact myself; he was not making it up. A couple interesting static stories.

 

[iwire]

Charlie very nice description of the difference between a static shock and a 'real' shock. 8)

I can tell you 277 feels like getting hit by a car and it stays with you for a bit.

 

[ceknight]

I don't have anything to add to this thread, but in case you missed this story .... http://news.bbc.co.uk/1/hi/world/asia-pacific/4252692.stm

:shock:


Chris Knight
Syracuse NY

 

[onlyinamerica]

uh, geesh guys, I was just asking if I maybe had a grounding problem. Didn't know I was going to get the whole suppositories/helicopter/fire/40,000volt issues thrown at me. :lol: Guess I'm okay. I can still zap the wife and dog though but only if I'm not wearing a nylon jacket and a wool shirt! :lol:

Thanks!

Dan