240 volt GFCI no neutral tripping

[jyork89]

I have a well pump on a 240volt 20 amp GFCI breaker that will not hold. It held on a regular 2p20 for over a year. This well pump set up has a bladder with a solenoid pressure reg valve, controller with a capacitor, and about 500 feet of total length for conductor. I have about .2 amps between phases on start up. (27.38A and 27.58A). The pump is a 3 wire (two hots and a yellow). I have continuity between both legs plus both legs and the yellow wire. Ohms between legs is 13.8 ohms, leg 1 - yellow is 11 ohms, leg 2 to yellow is 3ohms. I have zero experience with well pumps let alone pumps with controllers with a capacitor and bladder solenoid pressure reg valve controlling the pump.

Any and all assistance will be greatly appreciated.

 

[retirede]

Why was this circuit put on a GFCI breaker?

 

[mbrooke]

I have bout 500 feet of total length for conductor.

At 500 feet line to ground capacitance is likely to cause inadvertent trips.


However, depending on what size wire is run to the well pump you may need to GFCI or GFP breaker in order to trip for a ground fault at the pump.

 

[ptonsparky]

Yes, why is it on a GFCI?

Ground Fault Circuit Interruption looks for ground faults. They don’t care what the resistance of each load wire is to the other. They don’t care if a capacitor is in the circuit or how it’s controlled. It is looking for a current imbalance on the load.

Meg the wires to ground or earth.

 

[mbrooke]

Yes, why is it on a GFCI?

Ground Fault Circuit Interruption looks for ground faults. They don’t care what the resistance of each load wire is to the other. They don’t care if a capacitor is in the circuit or how it’s controlled. It is looking for a current imbalance on the load.

Meg the wires to ground or earth.

Megging won't measure pico farads to earth.

 

[ptonsparky]

Megging won't measure pico farads to earth.

That’s why you don’t put them on a GFCI.

Use GFP if it’s deemed necessary for some odd reason. In the past Franklin suggested enclosing all the conductors including the EG in the sensing coil. No trip until the fault current was excessive to earth, not just the EG.

 

[mbrooke]

That’s why you don’t put them on a GFCI.

Use GFP if it’s deemed necessary for some odd reason. In the past Franklin suggested enclosing all the conductors including the EG in the sensing coil. No trip until the fault current was excessive to earth, not just the EG.

Yup- agree.

But the run length here if not upsized for VD might force a GFP device.

 

[ptonsparky]

Yup- agree.

But the run length here if not upsized for VD might force a GFP device.

Franklin has pretty extensive charts indicating wire sizes for each motor, voltage, phase and distance. IDK about the others. I do not recall even a suggestion that GFP is required.

 

[winnie]

Question 1: Two hots and a yellow? Is there even an EGC?

Use GFP if it’s deemed necessary for some odd reason. In the past Franklin suggested enclosing all the conductors including the EG in the sensing coil. No trip until the fault current was excessive to earth, not just the EG.

It appears that Franklin still suggests this:

Franklin AIM | Franklin Water

Franklin AIM

franklinwater.com

" When an installation has abnormally corrosive water AND the drop pipe or casing is plastic, Franklin Electric recommends the use of a GFCI with a 10 mA set-point. In this case, the motor ground wire should be routed through the current-sensing device along with the motor power leads. Wired this way, the GFCI will trip only when a ground fault has occurred AND the motor ground wire is no longer functional. "

 

[retirede]

Question 1: Two hots and a yellow? Is there even an EGC?



It appears that Franklin still suggests this:

Franklin AIM | Franklin Water

Franklin AIM

franklinwater.com

" When an installation has abnormally corrosive water AND the drop pipe or casing is plastic, Franklin Electric recommends the use of a GFCI with a 10 mA set-point. In this case, the motor ground wire should be routed through the current-sensing device along with the motor power leads. Wired this way, the GFCI will trip only when a ground fault has occurred AND the motor ground wire is no longer functional. "

Does such a device exist?

 

[ptonsparky]

Does such a device exist?

this: https://www.automationdirect.com/ad...coders/ground_fault_sensors/gfsl30-m1b-120a-f

 

[retirede]

this: https://www.automationdirect.com/ad...coders/ground_fault_sensors/gfsl30-m1b-120a-f

Interesting....so to use it per Franklin’s instructions, you simply run the EGC through the port along with current-carrying conductors.

Learned something! Thanks

 

[jyork89]

210.8F requires GFCI for all exterior outlets

Why was this circuit put on a GFCI breaker?

The well pump was temped in with a standard 2P20 during construction under the 2017 NEC cycle. The final is under the 2020 NEC and the AHJ is fighting me on the continuation of the 2017 NEC

 

[jyork89]

Yup- agree.

But the run length here if not upsized for VD might force a GFP device.

The well pump conductors are #10AWG and that is the majority of the run.

 

[jyork89]

Question 1: Two hots and a yellow? Is there even an EGC?



It appears that Franklin still suggests this:

Franklin AIM | Franklin Water

Franklin AIM

franklinwater.com

" When an installation has abnormally corrosive water AND the drop pipe or casing is plastic, Franklin Electric recommends the use of a GFCI with a 10 mA set-point. In this case, the motor ground wire should be routed through the current-sensing device along with the motor power leads. Wired this way, the GFCI will trip only when a ground fault has occurred AND the motor ground wire is no longer functional. "

Yes there is a ground.

 

[ptonsparky]

210.8F requires GFCI for all exterior outlets

The well pump was temped in with a standard 2P20 during construction under the 2017 NEC cycle. The final is under the 2020 NEC and the AHJ is fighting me on the continuation of the 2017 NEC

Hard wire it.

 

[jyork89]

Thank you all for input on this.

Hard wire it.

It is hard wired.

 

[retirede]

210.8F requires GFCI for all exterior outlets

The well pump was temped in with a standard 2P20 during construction under the 2017 NEC cycle. The final is under the 2020 NEC and the AHJ is fighting me on the continuation of the 2017 NEC

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.

 

[winnie]

I general I am of the opinion that if a modern piece of equipment has enough leakage current to trip a GFCI, that piece of equipment is broken.

In this particular case (long run of wire underground) I could imagine that capacitive leakage through perfect insulation would be sufficient to trip a class A GFCI, so I am inclined to give the benefit of the doubt.

My next diagnostic test would be to measure the leakage current, and decide my next step based upon that measurement. If leakage was small and 'reasonable' given things such as capacitive coupling, then I would try to adjust the application to not require GFCI protection, or determine if less sensitive GFPE would be more suitable.

If leakage were large then I would look at getting the equipment repaired or replaced.

I believe that manufacturers often suggest the short cut 'remove the GFCI' rather than fix their products.

-Jon

 

[winnie]

Is 210.8F referring to all outlets or just receptacle outlets? I’m not on 2020.

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