revisiting the gfci

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DLB
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Re: revisiting the gfci

Post by DLB »

beeg wrote: Wed Jan 26, 2022 6:42 pm Doesn't a person have to be a path to ground, to be electrocuted ? No ground,no flow of electricity.
No, they do not. A person can be in contact with any two items with a voltage differential and be shocked. If the shock current is high enough, the person can be electrocuted. In U.S. household wiring ground is not used for normal current flow. But current will flow to ground if a resistor (including human) comes in contact with a hot conductor and ground because the voltage differential is there.

But a ground path is common for severe shock, including electrocution, and the only one that GFCI protects against. Per NEC, GFCI is mostly required in "wet areas" (includes potentially wet). The presence of water greatly decreases the human's electrical resistance, effectively increasing current in the presence of electricity. Most of our normal high resistance comes from the outer dry skin layers. I just checked mine, 20 Meg Ohms from left hand finger tip to right hand finger tip, dropped to less than 200 K when I wet my finder tips, a ~99% reduction. Which is a 100X increase in current if I get shocked. The presence of water may also provide the ground path or reduce the resistance of other materials between the human and ground.

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garys
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Re: revisiting the gfci

Post by garys »

I have to play stupid here. Looking at the drawings, I can't tell how that GFI is supposedly connected. Mine all have two terminals for line and two more for load. Nothing in the picture is labeled so I can identify it.
Hobbyman2
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Re: revisiting the gfci

Post by Hobbyman2 »

garys wrote: Thu Jan 27, 2022 12:36 pm I have to play stupid here. Looking at the drawings, I can't tell how that GFI is supposedly connected. Mine all have two terminals for line and two more for load. Nothing in the picture is labeled so I can identify it.
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there is no GFCI protection regarding the line or load , even if a GFCI breaker is used , the stick person has entered into a series circuit , the GFCI reacts as if the stick person is a lightbulb not a ground fault , with out a ground fault or a over current reaction there is not ground fault protection .
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Hobbyman2
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Re: revisiting the gfci

Post by Hobbyman2 »

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beeg
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Re: revisiting the gfci

Post by beeg »

garys wrote: Thu Jan 27, 2022 12:36 pm I have to play stupid here. Looking at the drawings, I can't tell how that GFI is supposedly connected. Mine all have two terminals for line and two more for load. Nothing in the picture is labeled so I can identify it.
If ya find the light bulb, that's the load side.
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garys
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Re: revisiting the gfci

Post by garys »

But, I'm seeing a line on each side from line to load. Does that mean they are connected together?
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Re: revisiting the gfci

Post by john_001 »

garys wrote: Thu Jan 27, 2022 2:02 pm But, I'm seeing a line on each side from line to load. Does that mean they are connected together?
Yes. If you're just installing a GFCI outlet by itself, you connect the cable to the "line" terminals; the "load" terminals are unused. When you're continuing the circuit on to other outlets, they're connected to the "load" terminals. That way, several outlets can be daisy-chained downstream from a single GFCI and they'll all be protected, provided the GFCI is the first one.
garys
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Re: revisiting the gfci

Post by garys »

The drawing shows the line and load sides connected together. You never do that.
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Re: revisiting the gfci

Post by Hobbyman2 »

garys wrote: Thu Jan 27, 2022 5:15 pm The drawing shows the line and load sides connected together. You never do that.
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you are correct , the drawing does not show the bare ground either.
That said
They are connected internally . you can receive shock from the load side when power is connected to the line side , this is why they cover them in yellow protective caution tape . if there are no devices down stream on the load side there is no need to remove the tape . :)
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Re: revisiting the gfci

Post by Hobbyman2 »

One thing to also keep in mind is amp draw can = death, the GFCI over current protection will only trip after a given time of over current use , it takes is less than 1/2 noncontinuous amps to kill a person . to stop a beating heart .
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