240V GFCI, No EGC

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Lioneye

Lioneye

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Location
Northwest USA
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Master Electrician, State Electrical Inspector
Hi,
I have a customer with an existing 240V, 30A well pump circuit, installed 80' remote from a residence. Installed 30 yrs ago, underground 10/2 UF cable, with"No Equipment Grounding Conductor" (Yup... confirmed at both ends). As such, we have phase to phase OCP, but no phase to ground protection. Can a 2-pole GFCI breaker with no connection the the neutral or ground bar in the service, capture and react to a phase to ground event at the load end? Prob still equal current if the circuit is closed, but it when it opens would it trip? I know the breakers need a neutral connection (st the panel) for the test function to work... Any insight would be appreciated, especially if it has some documentation I can pass along. Panel is a 200 A, Homeline.
Thanks!!
 
I know that is the case with 120V devices, just hadn't seen any documentation regarding 240V, 1-ph.
 
Is it actually UF cable? Or pump wire? Must be pretty old for UF not to have a egc. If it’s that old, I think your going to have issues with the gfi tripping due to cable leakage.
 
Here’s a pic that may explain it all...
1579485661951.jpeg


the ring in the breaker is a CT.

from the article
”The white “pigtail” wire on a GFCI circuit breaker serves two functions. It completes the connection to the panel neutral bar for the neutral load conductor and also completes the power supply circuit for the electronics. This means that even in installations where there is no load neutral conductor, the white pigtail wire must still be connected to the neutral bar in the load center or panelboard in order for the electronic ground-fault protection circuit to function. (Note: Some manufacturers may offer circuit-breaker GFCIs with a plug-on neutral connection rather than a pigtail.)”
 
As mentioned, if the cable is that old you likely will have enough leakage to trip a GFCI let alone the likely leakage in the pump.
But a GFCI is not a solution in any event as it does not meet code. Electrically floating well cases have been the cause of numerous deaths over the years. So much so that the code some cycles back added a specific a requirement to make clear that the well case must be bonded to the EGC.
 
texie said:
As mentioned, if the cable is that old you likely will have enough leakage to trip a GFCI let alone the likely leakage in the pump.
But a GFCI is not a solution in any event as it does not meet code. Electrically floating well cases have been the cause of numerous deaths over the years. So much so that the code some cycles back added a specific a requirement to make clear that the well case must be bonded to the EGC.
Click to expand...
I wonder if the UF's EGC has deteriorated internally to where he can no longer see it with the phase conductors? I know here in Florida I've had the EGC essentially break off at the base of the cable, well water leaked down the cable assembly and destroyed the conductor.
 
Lioneye said:
Hi,
I have a customer with an existing 240V, 30A well pump circuit, installed 80' remote from a residence. Installed 30 yrs ago, underground 10/2 UF cable, with"No Equipment Grounding Conductor" (Yup... confirmed at both ends). As such, we have phase to phase OCP, but no phase to ground protection. Can a 2-pole GFCI breaker with no connection the the neutral or ground bar in the service, capture and react to a phase to ground event at the load end? Prob still equal current if the circuit is closed, but it when it opens would it trip? I know the breakers need a neutral connection (st the panel) for the test function to work... Any insight would be appreciated, especially if it has some documentation I can pass along. Panel is a 200 A, Homeline.
Thanks!!
Click to expand...
I feel the OCPD would trip at the "imbalance" but during a phase to ground, I would have to say it would never open, theres no reference to earth at the load end what ever its connected to would just stay energized, you COULD maybe put a 240-120/240 transformer and put a GFCI breaker in the sub panel, and then run an EGC from that sub to the equipment then the OCPD would trip out side, as for the original circuit with out redoing it all no EGC would be present at the transformer then you run in to another problem lol!
 
anthonysolino said:
I feel the OCPD would trip at the "imbalance" but during a phase to ground, I would have to say it would never open, theres no reference to earth at the load end what ever its connected to would just stay energized, .........
Click to expand...

GFCI's don't even need a load to operate when a ground fault occurs. A simple buried UF that's been abandoned with an energized conductor in contact with the earth will eventually trip a GFCI.
 
Thanks everyone. Great info. I see how the 120v, 2-wire GFCI work by “comparing” the hot and neut. no EGC needed. In this case though we’re looking at a 240v 2-wire no neut and no EGC. And yes, we peeled back jacket at ea end. No EGC. So my opinion was that a GFCI would not work, as it had no conn to egc (or neut) at the load. Homeowner isn’t responsive to problem (We’re running that down with the AHJ), but fit the renters sake, with small kids, we want to see this resolved. From a short term and cost standpoint, I was hoping to gather into to support or dismiss a GFCI solution as opposed to trenching in a new line. Which may happen. Just not an easy task, with distance and rockeries in the way. They may just have to pony up a buck fifty for a breaker and we’ll try it. Keep those ideas coming!
Thanks, again.
 
Lioneye said:
Thanks everyone. Great info. I see how the 120v, 2-wire GFCI work by “comparing” the hot and neut. no EGC needed. In this case though we’re looking at a 240v 2-wire no neut and no EGC. And yes, we peeled back jacket at ea end. No EGC. So my opinion was that a GFCI would not work, as it had no conn to egc (or neut) at the load. Homeowner isn’t responsive to problem (We’re running that down with the AHJ), but fit the renters sake, with small kids, we want to see this resolved. From a short term and cost standpoint, I was hoping to gather into to support or dismiss a GFCI solution as opposed to trenching in a new line. Which may happen. Just not an easy task, with distance and rockeries in the way. They may just have to pony up a buck fifty for a breaker and we’ll try it. Keep those ideas coming!
Thanks, again.
Click to expand...

If power is going out on the ungrounded (hot), and doesn't come back on either the grounded (neutral) or other ungrounded, the GFCI will detect this and trip.

No EGC or grounded at the load is needed. Nor is a load even needed. Current going out, but not coming back, is the definition of a ground fault.
 
So, to recap, the GFCI device itself needs a neutral connection to function. It will function as protection as designed with no EGC "reference" at the load end. If a contact is made through a person to earth, the GFCI should trip as usual.

The concerns mentioned seem to suggest that a GFCI will not function without a ground at the load end. This is not correct. If enough current can flow to shock (the 4-to-6 ma) with 80' of earth in the pathway, the GFCI should function.
 
480sparky said:
GFCI's don't even need a load to operate when a ground fault occurs. A simple buried UF that's been abandoned with an energized conductor in contact with the earth will eventually trip a GFCI.
Click to expand...
when I said ground fault I was referring to a phase to equipment fault if the equipment is not bonded I don't see how a "fault" event would ever occur I would suppose that when the load was turned on the OCPD would see an imbalance due to the phase being landed on the equipment thus creating more resistance?, with no load would it fall back on the idea you can take a phase conductor and push it in the dirt and it will never open a breaker, I was thinking that in his case the load equipment
 
LarryFine said:
So, to recap, the GFCI device itself needs a neutral connection to function. It will function as protection as designed with no EGC "reference" at the load end. If a contact is made through a person to earth, the GFCI should trip as usual.

The concerns mentioned seem to suggest that a GFCI will not function without a ground at the load end. This is not correct. If enough current can flow to shock (the 4-to-6 ma) with 80' of earth in the pathway, the GFCI should function.
Click to expand...
It should function all day long as far as a phase to equipment fault, where a conductor makes contact with the equipment that has no bond to the EGC how would the breaker open?
 
anthonysolino said:
...........when I said ground fault I was referring to a phase to equipment fault if the equipment is not bonded I don't see how a "fault" event would ever occur I would suppose that when the load was turned on the OCPD would see an imbalance due to the phase being landed on the equipment thus creating more resistance?, with no load would it fall back on the idea you can take a phase conductor and push it in the dirt and it will never open a breaker, I was thinking that in his case the load equipment
Click to expand...

It's still a ground fault, but if the equipment doesn't have a path to ground, then it simply becomes energized. But once a path is created (i.e., some poor slob who's grounded touches it), the GFCI will trip when enough current flows.

anthonysolino said:
.......with no load would it fall back on the idea you can take a phase conductor and push it in the dirt and it will never open a breaker, I was thinking that in his case the load equipment
Click to expand...

A standard non-GFCI breaker... no, sticking the hot wire into the ground won't trip it. It probably will trip a GFCI though... unless the dirt is dry as a bone.
 
** the earth shall never be used as an effective fault current path. the EGC is critical
480sparky said:
It's still a ground fault, but if the equipment doesn't have a path to ground, then it simply becomes energized. But once a path is created (i.e., some poor slob who's grounded touches it), the GFCI will trip when enough current flows.



A standard non-GFCI breaker... no, sticking the hot wire into the ground won't trip it. It probably will trip a GFCI though... unless the dirt is dry as a bone.
Click to expand...
I would concur, I THINK its just a thought that IF a phase landed on the equipment that has NO EGC present, once the load is placed, the GFCI may trip due to the higher resistance thus creating more current on one phase, Then the breaker should function, it wouldn't trip under the notion of a "Dead short" but that of a imbalanced load Due to the increased resistance of the "Dead short" condition. does it seem plausable?
 
Again, great thoughts. It’s nice to be able to bounce this off of some intelligent sources. The more I think about it and read the replies above, I think that indeed a two pole GFCI would work. Looks like the next step is to install one and see if we can create a test.
 
anthonysolino said:
when I said ground fault I was referring to a phase to equipment fault if the equipment is not bonded I don't see how a "fault" event would ever occur I would suppose that when the load was turned on the OCPD would see an imbalance due to the phase being landed on the equipment thus creating more resistance?, with no load would it fall back on the idea you can take a phase conductor and push it in the dirt and it will never open a breaker, I was thinking that in his case the load equipment
Click to expand...
A standard breaker would not trip with a phase-to-equipment fault with only the earth in the pathway, and voltage gradients would create a great shock hazard at the well.

A GFCI device, on the other hand, would trip if the leakage current reached the threshold level. If that level is not reached until a person receives a shock, it will trip at that time.

That's why a GFCI is an acceptable substitute for a circuit without an EGC. Whether one or neither conductor is grounded only changes the quantity of shock-causing wires.
 
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