Possible Explanations Requested

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charlie b

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I have a few possible explanations myself, all of which are unlikely. So I?d like to ask for opinions.

About a week ago, while flipping the switch to turn on an item plugged into a kitchen SA circuit, I received a shock. I think that I felt the shock only in my hand, but these sorts of unexpected events do not always make you a keen observer of details. I pulled my hand away, and cursed myself for having touched the switch with wet hands. Then I asked myself why the GFCI did not trip.

The receptacle in question was fed downstream from a GFCI receptacle that I paid an electrician to install about a year ago. The house is 60+ years old, and many receptacles do not have EGCs connected. I have not opened this one, or the upstream GFCI receptacle, to discover whether either has an EGC connected.

I went to the ?Big Blue store,? and bought a plug-in GFCI tester. Plugging it in to the receptacle in question, I saw two yellow lights (i.e., correct wiring). Then I hit the test button, and the GFCI receptacle tripped.

So I still wonder why this GFCI did not trip during the time I was feeling the shock. I also wonder whether it would trip, if there were a future need.

Any ideas (before I list my unlikely ones)?
 
Wouldn't the answer be that the GFI is comparing current through the hot and the neutral. If there is any difference (in the milliamp range) the rec. trips. In your case the recept. had no difference in current between the two wires (Hot and Neut.) so it didn't operate. Glad to see that you are alright! You have helped me out tremendously with your posts.

Regards.
 
Charlie, starting with the premise that the GFCI is operating properly, two possibilities come to mind:

1) The shock you received was not strong enough to reach the trip-point of the device.

2) The current path was out of, and back into, the switch, and not through your body.

(#2 is what I believe Mr. Snyder was alluding to.)
 
I am closing this post, in accordance with the Forum’s rules. This Forum is for professional electricians, inspectors and other members of the electrical industry. We are not permitted to provide “how-to” assistance to a person who is not employed in this industry.

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Sorry...had to get off my chest :)



charlie b said:
Any ideas (before I list my unlikely ones)?
Are you SURE you got a shock?
This may seem like a bizarre question to ask you, but haven't you ever touched a piece of equipment - energized or not - and by some fluke of human nature, managed to have your arm contorted in just the right position to "assume" you just got rapped?
I did just this the other night while soldered a water pipe.
 
GFCI does not prevent shock, they are designed to prevent electrocution. It is very possible that you received enough current that it was perceived (especially since your hands were wet) but not enough to trip the GFCI. It is also possible that the switch is wired from the line side of the GFCI and not protected by the device. More investigation is needed. Let us know.
 
celtic said:

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Sorry...had to get off my chest :)

Touche'!

Are you SURE you got a shock?
This may seem like a bizarre question to ask you, but haven't you ever touched a piece of equipment - energized or not - and by some fluke of human nature, managed to have your arm contorted in just the right position to "assume" you just got rapped?
I did just this the other night while soldered a water pipe.

I've had this happen to me, but I'm not guessing that's what happened here.

If I were a betting woman (which we've managed to establish in previous threads that I am :cool: ), I'd look to see what kind of ground, if any, were present in the switch's junction box, what the ground lug of the switch (if one) is attached to, and where the EGC in that box (if one exists ...) goes.

Whatever the answer, it sounds like Charlie needs to have an electrician stare at it, and possibly double check his collection of Lucky Rabbit Feet, Four-Leaf Clovers, and pieces of toast with images of famous people on them.
 
Did I read this correct. Charlie paid someone else to install a GFI? Can you imagine working for Charlie. Betcha the electrician lost his but on that one. Two days to install a GFI. (the right way):D :D
 
a) Static charge? b) you got in-line/in-series of a 2wire appliance c) as Celtic said, you had a muscle spasm/twitch d) you're going nuts. By the way I've got kids & grandkids up your way, if you pay the travel I'll troubleshoot & repair it for free!! and yes I'm certified in WA.
 
Many thanks for all the responses, including the ones poking fun my way.

sceepe said:
Did I read this correct. Charlie paid someone else to install a GFI? Can you imagine working for Charlie. Betcha the electrician lost his but on that one. Two days to install a GFI. (the right way)

It was only one day, and the work scope included a service panel replacement and a handful of other minor repairs. But I ain?t no fool. I was at work all day, and came home after the work was done, to meet with the Inspector and to pay the bill.

tlaidman said:
It is possible since you got shocked off the switch that the switch is upstream of the GFCI and not protected
AND

haskindm said:
It is also possible that the switch is wired from the line side of the GFCI and not protected by the device.

This was a plug& cord connected item.

rdelauter said:
Did the item you were planning to operate have a ground?
It did not. It was a fluorescent light fixture, and it has a two-prong cord.

celtic said:
I am closing this post, in accordance with the Forum?s rules. This Forum is for professional electricians, inspectors and other members of the electrical industry. We are not permitted to provide ?how-to? assistance to a person who is not employed in this industry.

Now come on, give a guy a break. Did I ask for ?how to? advice? A DIY asking ?what happened? is not against Forum rules. :wink:

celtic said:
Are you SURE you got a shock?

I am sure. Been there; done that. But I don?t want to talk about those guys in the white coats. :roll:

haskindm said:
It is very possible that you received enough current that it was perceived (especially since your hands were wet) but not enough to trip the GFCI.

Actually, I believe this is the most likely answer. I looked through my notes for an Electrical Theory class I presented a few years back. The threshold for perception of shock is around 1 milliamp. It starts getting distressing, if not actually painful, around 4 milliamps. A GFCI is designed to trip between 3 to 5 milliamps.

tallgirl said:
. . . it sounds like Charlie needs to have an electrician stare at it, and possibly double check his collection of Lucky Rabbit Feet, Four-Leaf Clovers, and pieces of toast with images of famous people on them.

I was hoping to get some assurances that the GFCI is working properly, that the ?GFCI Tester? did not lie to me. I am happier now. You are right about the rabbit?s foot and four-leaf clovers. But the toast is a new one to me.

Once again, thanks to all.

NOTE TO SELF: Don?t touch electrical stuff with wet hands. :)
 
charlie b said:
Many thanks for all the responses, including the ones poking fun my way.
It's not often the peons get to attack one of the king's men about the ankles....carpe diem ...LOL :D



 
ron said:
I got one heck of a whopper of a shock from the door of my car yesterday.
I thought that was just me and all my positive charge :D

I get a good blast EVERY time I open/close the door to my truck:mad:
 
celtic said:
I thought that was just me and all my positive charge :D


Two electrons are walking down the street.

One says, "I lost an electron!"

Second one says, "Are you sure?"

First one says, "I'm positive!"
 
might be that the current was enough to 'shock' but not enough to trip.
saw somewhere that a miniscule amount of current is enough to elicit a violent reaction. it was less than 20 milliamp, if I remeber correctly
 
robbietan said:
might be that the current was enough to 'shock' but not enough to trip.
saw somewhere that a miniscule amount of current is enough to elicit a violent reaction. it was less than 20 milliamp, if I remeber correctly

Do you have any idea how much amperage (not considered any other factors) it *could* take to kill a person?
 
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