240 volt GFCI no neutral tripping

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Don't the installation instructions for a GFCI limit the number of feet past the GFCI?
I thought I ran into this years ago
 
retirede said:
Generally, the code in effect when the permit is pulled is what gets enforced. It can be hard to hit a moving target.

Is 210.8F referring to all outlets or just receptacle outlets? I’m not on 2020.
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I agree! This particular project was originally pulled under a state permit. Do to reason too long to explain the county decided to take over inspections in this area. When they did that the we had to pull a final permit through the county in the 2020 cycle. I haven't pushed too hard yet. The project owner is a little nervous of me ruffling the feathers until necessary.
 
Seems to me if the yellow wire is used as EGC (which many times it is unless it is connected to a start controller) your readings from leg to this yellow (ground) should not be 3-11 ohms. You have a ground fault!
It could be, if the pump has been installed for several years that if the wire leading down to the pump has not been taped often to the down pipe it can get lodged and rubbed against the well casing every time the pump kicks in wears at it.
 
mopowr steve said:
Seems to me if the yellow wire is used as EGC (which many times it is unless it is connected to a start controller) your readings from leg to this yellow (ground) should not be 3-11 ohms. You have a ground fault!
It could be, if the pump has been installed for several years that if the wire leading down to the pump has not been taped often to the down pipe it can get lodged and rubbed against the well casing every time the pump kicks in wears at it.
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The yellow wire is not the EG. It is a motor lead.
 
This post serves as a good example of how out of touch the CMPs are with the real world. They have gotten into the habit of requiring things that either are not yet available or not reliable. I don't see how you could expect a class A GFCI to work in this situation or for the submersible manufacturer to support this.
I think this also raises a question of "outlet" definition as it applies to the typical submersible pump in a well in a residential setting. In most cases the "outlet" is within the structure and the branch circuit extends from that "outlet" directly to the well head. In other words the outlet is not outdoors as the first word of 210.8(F) says.
 
jyork89 said:
The well pump conductors are #10AWG and that is the majority of the run.
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1.2 omhs per 1000 feet = a 1.2 ohm ground fault current loop or 100 amps short circuit current at the well pump at 120 volts.


That would tally up to a 9 second disconnection time:

https://library.industrialsolutions...t Curves|GES-6202A|PDF&filename=GES-6202A.pdf

Considering that a concentric voltage gradient would form around the casing, the touch voltage may be lower than 60 volts.



winnie said:

210.8(F) GFCI Protection. Outdoor Outlets.

An “Outlet”, according to the NEC Article 100 definition, is a point on the wiring system at which current is taken to supply utilization equipment.
www.electricallicenserenewal.com

IMHO this is an excessive requirement for underground wiring to a submersible pump (unless that pump is in a body of water where people swim), but it appears to be required under 2020 code.

I amend my last post to 'if the leakage were reasonable given such things as expected leakage from capacitive coupling, then I would request a waiver from the AHJ to use GFPE rather than GFCI'.

-Jon
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The CMP's inference is trying to cover all cases like my reply above, especially where the run is not upsized or goes past 500 feet.

In reality their solution just won't work in the real world.
 
jyork89 said:
Hmm I don't know but I'll check
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They typically do, thanks to this equation:

1618170583945.png


Even if the breaker holds on the initial capacitive charging current and steady state current any switching transients create high frequency ripple which produces relatively large currents to ground tripping the GFCI. 30 and 50ma pickups help, but even then with long enough runs mixed with contacts opening at the right time results in tripping.

One will quickly realize the CMPs have a poor grasp of electrical theory amalgamated with a gaps in real world practices.
 
ptonsparky said:
Then politely ask your inspector to quote the article you are violating.
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jyork89 said:
article 210.8F there is a jbox on the top of the well head.
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texie said:
I think this also raises a question of "outlet" definition as it applies to the typical submersible pump in a well in a residential setting. In most cases the "outlet" is within the structure and the branch circuit extends from that "outlet" directly to the well head. In other words the outlet is not outdoors as the first word of 210.8(F) says.
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I agree that the "outlet" is not outdoors in this situation.
In a residential well system there is equipment that functions as a pressure controlled motor starter, and it's typically located inside of the home. This equipment could be a pressure switch for a 2-wire pump, or in the OP's case it would likely also include a capacitor, relay, etc. for a 3-wire pump. The way I see it these components are an essential portion of the "utilization equipment" itself, and not part of the branch circuit which supplies the power to it. And so the outlet, which is the "point on the wiring system at which current is taken to supply utilization equipment" would be upstream of this motor starter and control equipment, and therefore likely to be inside of the home.

Some relevant Article 100 definitions:

Outlet. A point on the wiring system at which current is taken to supply utilization equipment.

Utilization equipment. Equipment that utilizes electric energy for electronic, electromechanical, chemical, heating, lighting, or similar purposes.

Equipment. A general term, including fittings, devices, appliances, luminaries, apparatus, machinery, and the like used as a part of, or in connection with, an electrical installation.

Branch Circuit. The circuit conductors between the final overcorrect device protecting the circuit and the outlet(s).
 
texie said:
This post serves as a good example of how out of touch the CMPs are with the real world. They have gotten into the habit of requiring things that either are not yet available or not reliable. I don't see how you could expect a class A GFCI to work in this situation or for the submersible manufacturer to support this.
I think this also raises a question of "outlet" definition as it applies to the typical submersible pump in a well in a residential setting. In most cases the "outlet" is within the structure and the branch circuit extends from that "outlet" directly to the well head. In other words the outlet is not outdoors as the first word of 210.8(F) says.
Click to expand...


Bingo! Credit goes to you as you said it first. CMPs are out of touch with reality (y) If only reasoning through litigation actually worked...
 
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