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Posted By: Format_C: Is this normal? - 02/13/03 08:07 AM
Cat pucked on my slipers so i'm wearing socks now. So hear is my question is it normal to get a shock while turnig off/on the lights.(I usually always come into contact with the screw on the plastic plate). This only happens on carpet
Posted By: Scott35 Re: Is this normal? - 02/13/03 09:06 AM
Yer' gettin zapped by good ol' ESD! (Electro-Static Discharge).

Would have imagined that wearing only socks wouldn't build up a high charge (the socks wouldn't scrape charges off the carpet like the sole of a shoe or slipper will), however, the socks are most likely made of the same material as shoe and slipper soles (HDPE, rubberized nylon or polyester, ???) and this would scrape the Carpet when you take a step, pulling off some negative charges in the process.

Whatever the material is, it's obviously more Positive than the Carpet's material! - hence the "TICK"-OWWWCH experienced when touching something metallic.

Must be dry and possibly windy in your area (or your heater is really kicking A*%).

Before I go too much farther, you are certain this is not a 120 VAC bite??? I know this is a silly Q, but it's possible.

Fun stuff to do with ESD (besides discharging yourself into the nearest person... hee-hee):

Get a fairly new Fluorescent Tube - like an F32 T-8 (I have been successful with the older model F40 T-12 "Energy Savers" - 34 watts and 4100 K color / cool white).

Turn off lights and / or close curtains - making the room as dark as possible.

Put on your most "Shocking" shoes (any shoes that you own which cause ESD just by being near the carpet [Linked Image]...).

With the room dark, the shocking shoes on and the T-# Lamp held near one end, start scraping your feet really hard on the carpet (just don't let your wife see this, or she may use the T-# lamp in another fashion! :eek [Linked Image].
While you scrape your feet, the lamp will glow. See how far up the tube you can get the glow to go, and also how bright you can get it.

After doing this, join a social club - you have way too much free time on your hands [Linked Image]
<Joking>

First experience of this for me was on an office complex which was inside a warm and dry Tilt-Up building, plus during a Warm Santa Ana condition (Santa Ana winds).
The rooms had just been carpeted with the typical glue down low pile Commercial carpet.
I was Lamping 2x4s in offices when first noticed the glowing lamp situation.

That was a really shockee day! Was so strong at times I could blast a good 1/16" wide arc onto something / someone (OWWW!!!).

Scott35 S.E.T.
Posted By: Format_C: Re: Is this normal? - 02/13/03 09:59 AM
Must just be ESD then because I turned off the CB and it still happens. Guess the electrical system is well grounded.
Posted By: ElectricAL Re: Is this normal? - 02/13/03 12:24 PM
Just a thought,

Up here in frigid Minnesota, the ESD season is in full charge. Winter's extremely dry cold air depletes the humidity of many dwellings, contributing to static buildup.

If your computer is in a carpeted area, consider touching a part of the electrical system such as the light switch cover plate screws for a moment prior to touching any of the computer's parts.

I learned the hard way not to go straight to the keyboard. [Linked Image]
Posted By: sabrown Re: Is this normal? - 02/13/03 02:33 PM
One thing that can help with ESD is taking a diluted Downey mixture (that is water mixed with the laundry anti-static stuff) in a spray bottle and spray a fine mist over the carpet. You may have to experiment with the mixture (try a 10-20% Downey mix)and may need to apply it once or twice a month during the troublesome times.

Be careful not to over do this as the carpet may develop a tendency to need cleaning more often.

Shane
Posted By: Len_B Re: Is this normal? - 02/13/03 04:27 PM
Sounds like you've got a good ground at least.
Quote
Cat pucked on my slipers so i'm wearing socks now...
I'd discharge the electrostatic charge on its nose!

Mee---oooooow----ch!

Len

[This message has been edited by Len_B (edited 02-13-2003).]
Posted By: Anonymous Re: Is this normal? - 02/14/03 03:25 AM
Try using a shop vac on concrete while wearing rubber soles. I did this the other day and when I got close to the aluminum siding I got a zap so hard for a moment I thought the siding was energized.
Posted By: cubby964 Re: Is this normal? - 02/14/03 04:32 PM
When I was young, we would put on wool sweaters in the summer, rub around on a trampoline mat, and with one of us "grounded" to the frame see how big a spark we could get from finger tip to finger tip. About three inches as I recall. Isn't air good for around 10,000 volts an inch?
Posted By: Len_B Re: Is this normal? - 02/14/03 05:55 PM
Ionization potential of DRY air, 0%RH, is about 20KV per inch. Normal "wet" air about 5 - 10Kv. Used to love that tingley feeling walking under the 230KV overhead bus bars at steel mill switchyard on humid days!
Posted By: cubby964 Re: Is this normal? - 02/14/03 06:27 PM
Thanks Len, BTW you can guess it was pretty dry.
Also, don't bother using a "volt-tic" under any 230kV lines either.
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