Well pump tripping GFCI

[admo]

Hello everyone, I have setup truck as generator (240v to generator port) for my home fine. I have a neutral switching transfer switch and can power lights and refrigerators and freezers fine (the open neutral issue is solved). My issue is a GFCI fault (as reported by the truck display) from my well pump immediately when it starts. The well pump is on a 30amp breaker and draws under 15 amps when running, but it's startup/inrush is ~34 amps. My initial thought was "well that's the problem" but my house 30amp breaker is not tripping for this well pump on grid power, additionally I'm seeing some large capacitors in the control box for the pump which I believe is to handle this inrush issue.

The core question I'm trying to solve before spending a lot of money is: my truck is displaying a GFCI fault message. I had thought the GFCI message in the truck was indicating a general breaker issue but doing more reading on these forums I'm seeing other people saying there is also an "overload" message. Does anyone know more detail on this and what specifically either message means?

I read some people use soft starters to smooth out motors with large inrush current issues but the well pump companies here don't know or don't want to talk about them. On the other hand the well pump is 30 years old and I presume out of spec if it is on a 30 amp breaker and can draw more than 30 amps. So I am trying to find ways to figure out if the issue is the inrush current or a true GFCI fault. A well pump with any shorts in its wire or housing would of course trip GFCI leading to me needing to replace the pump, while the in rush issue I might be able to solve with a soft starter but they also have some expense.

I don't have details on the well pump unfortunately, only that it was placed 360 feet down. Some internet reading suggests GFCI faults could also occur from extremely long wire runs but I don't know if 720 feet is considered "extremely long". I do have the full four wires running down the well.

Thank you to anyone who has tips, I have not been able to convince the electrician or well pump company to use their expertise to figure it out. I'm also a bit naive on electrical stuff so I wanted to be really sure before I take a crack at installing a soft starter.

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[Maquis]

It doesn’t surprise me that a 30 year old submersible pump has enough leakage to trip a GFCI.
One possibility is to use an isolation transformer such as this. It would take the truck’s GFCI completely out of the equation.
https://www.digikey.com/en/products/detail/solahd/HS5F7.5AS/10072569?

 

[Ricks Lightning]

I'm not an expert in well pumps, but am in sump pumps, ejector pumps, circulating pumps. The last thing you want on a pump is a gfci breaker. same with a fridge unless you want spoiled food. 30 year old pump is most likely the issue as the same think happens with submersible pumps that sit in the water for a long time.

Rick

 

[Firn]

Traditional house breakers don't trip immediately, which is why they can handle an inrush of 34 amps. The lightning on the other hand will immediately trip.

Soft starts are just for this purpose. It's not traditional for a well pump, which why the well guys don't know about it, but it's pretty common for HVAC systems so go talk to an HVAC guy.

In the end it think a soft start is just what you need.

 

[admo]

Firn's advice differs from Maquis' and returns back to the thought I had that there are different error messages from the Lightning when it disconnects the Pro Power. I am seeing a GFCI message but Firn you suggest something that I believe would be an overload message. If the GFCI message indicates a GFCI fault then a soft starter seems like it would not solve the problem.

This post on these forums triggered my wondering on this, I didn't realize there were two different error messages: https://www.f150lightningforum.com/...er-breaker-with-120v-welder.18452/post-370924

 

[admo]

Thank you both Maquis and Rick, for the information. I am reading up to figure out this isolation transformer thing. Part of the difficulty here is that I have no method to test and confirm either hypothesis (GFCI fault via short versus overloading the circuit) aside from the error message from the truck. I don't believe my multi-meter would show the kind of voltage drop that would trigger the GFCI (Also I hope I said these electrical things correctly).

Although If there is a nicer multi-meter out there that does show this kind of precision that would be cheaper than guessing and installing either solution.

 

[shelnian]

If you try to draw more than 7200 watts, pro-power cuts out and indicates you are drawing more power than it's rated for. You have to reduce the load and then hit the reset button on the Sync screen.

 

[hturnerfamily]

it can be somewhat aggravating and annoying when ProPower 'works', then cuts out right when you least expect it

- home-based breakers do NOT work the same exact way that our electronic-based circuits work within the LIGHTNING's ProPower. Regular breakers are based on 'heat', whereas electronic circuits are MUCH MORE EXACT... when they read 30+amps, they IMMEDIATELY trip. An 'in rush' when a compressor or similar motor starts up is problematic.

- the truck's circuitry can seem to be bypassed when it comes to the sensitivity of the GFCI 'issue', at least until you add a substantial LOAD. It seems the additional amperage tips the scales toward tripping.*

*one example: my camper.
Our previous campers we towed had no issues using ProPower, while towing or hooked up to the truck, even the air conditioner or microwave.
Interestingly, though, our newest camper, very similar to the previous two, will NOT work readily with ProPower, meaning that the truck's power shuts off immediately when plugging in the camper, while towing or hooked up to the truck.**
**The 'while towing', and/or 'hooked up to the truck', is ultimately the problem.
We all know the issue of the 'ground' wire. That connection was removed.
We all may also know the issue of the truck's GFCI not pairing well with other GFCI outlets, such as the one in my camper. I removed the GFCI outlet in favor of a 'regular' outlet.
These two changes created a solution, at least initially.

When I am NOT attached to the camper, my truck's ProPower can easily provide all the power I need, for EVERYTHING, and all at the Same Time. Sweet. It works the way it's supposed to.

When I AM attached to the camper, whether just the coupler on the ball, or the 7-pin 12v connector to the camper, if the breaker to the camper's 12v Converter is left ON, ProPower trips.
If, tho, I turn OFF this converter breaker, I can then use 'some' electricity in the camper...
when I turn on the microwave, or the air conditioner, though... bamm - I lose power, again.
It must be some type of 'grounding' issue with the camper, or it's Main Panel wiring, or, as I've surmised, the 12v CONVERTER wiring for the camper, to the camper's two batteries.

so, yes, it's aggravating, and maybe there is an ultimate solution, but, for now, I just use 'some' electricity, and if I need more, I completely unhook the camper from the truck, and everything works perfectly : )

 

[Heliian]

Yes, the inrush current causes a gfci fault. Your problem is the pump.
Soft start capacitor would probably fix it but if your pump is old and inefficient there will be no fixing it.
Inverters can have a really hard time with inrush.

 

[admo]

Thank you for the information hturnerfamily. Heliian it sounds like I am overthinking the meaning of these messages then.

So without a means to test any o the causes, and a need to get plumbing working during power outages it seems I will need to go through the suggestions here in order of price, with pump replacement last. I guess soft starter -> isolation transformer -> pump.

Does anyone know why one of the well companies said you have to replace the pump to install a soft starter? I would have thought a soft starter is an inline device and I could place it in the garage around the pump controller.

 

[shelnian]

Does anyone know why one of the well companies said you have to replace the pump to install a soft starter? I would have thought a soft starter is an inline device and I could place it in the garage around the pump controller.

Motors requiring very high starting torque might not function well with a soft starter due to reduced torque during startup. Don't believe most well water pumps require a very high starting torque because they use an impellor style pump.

 

[K6CCC]

- home-based breakers do NOT work the same exact way that our electronic-based circuits work within the LIGHTNING's ProPower. Regular breakers are based on 'heat',

To expand on this a little. Normal home based breakers will trip at slightly above their rating - EVENTUALLY. Obviously it depends on the breaker, but to trip a 30 amp breaker with a 34 amp load the trip time will likely be measured in a large number minutes or quite possible in hours. You want it to trip in less than one second, better put at least 10 times it's rating (maybe more). Look at the trip time charts for your breakers and most people are surprised.

With that said, a GFCI breaker WILL trip very fast in the event of a quite small difference between hot and neutral current (they don't actually measure ground current).

 

[admo]

Motors requiring very high starting torque might not function well with a soft starter due to reduced torque during startup. Don't believe most well water pumps require a very high starting torque because they use an impellor style pump.

This would explain then why there are lots of suggestions for these Grundfos well pumps on these forums. Alrighty, I shall focus on the isolation transformer Maquis suggested at the start, even if it does not solve the problem a lot of people are saying GFCI protection on a well pump is just a bad idea and this appears to be the only way to mitigate the truck's GFCI coverage.

Thanks shelnian.

 

[v2h8484]

As a *temporary* test to be more certain that GFCI is the main problem (vs inrush current) could be to disconnect the ground from the truck. If the main problem is actually inrush current then a large transformer can exacerbate the inrush current problem.

 

[admo]

As a *temporary* test to be more certain that GFCI is the main problem (vs inrush current) coulbe be to disconnect the ground from the truck. If the main problem is actually inrush current then a large transformer can exacerbate the inrush current problem.

Since we are way outside my knowledge here, how best would you propose doing that? Should I open the generator inlet plug box and find a way to remove the ground wire? Should I attach that ground wire to something else? There are inline plugs for this too I believe, is that a better option?

Lastly and most importantly suppose; what are the results of this test I should expect? If things work after doing this is that indicating that the GFCI is the issue? I'm confused myself on that because I thought GFCI was based on the flow through the live and neutral wires.

I understand this is not a safe thing to do and not a permanent solution.

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