Pro Power Ground Fault

[FLSpartan04]

I have been trying to get my Pro Power to function as backup power to my house unsuccessfully for a week or so now. Without getting into the arguments of how to back feed the house, I have set up the truck to feed through a L14-30R to an interlocked breaker in my main panel. A very helpful board member (@flyct ) has been helping me troubleshoot. It seemed everything was set up correctly in my panel but as soon as I would turn on 1 load, the pro power will fault (before anyone asks, ground is not a variable in this setup). Well in messaging back in forth, it turns out @flyct is my neighbor! He came by today to help me troubleshoot. Good news is we have isolated the problem, the bad news is it is my truck. He is able to feed power successfully from his truck to my panel, when we move the cable to my truck, pro power detects a ground fault.
A little more information, I seem to be able to power loads just fine plugging into the outlets directly on my truck. However I don’t have anything good to test a 230v load to be able to duplicate the problem for a service department to get warranty work done. I just ordered at @flyct ‘s suggestion a 230 to 110 splitter to try to simulate the condition. Has anyone else had issues with pro power? If so, if you have any information like a TSB or something else along those lines, that would be helpful!

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[TaxmanHog]

If your truck had spray in liner, it's possible the connectors for the output panel in the bed might not be seated sufficiently, IIRC they remove the panel when doing the liner install, then restore it once the coating has cured, other members have experienced it being completely disconnected.

 

[Mmiketa]

You probably have a loose ground somewhere in the truck. You could try to find it, or let the dealer do it for you.

 

[FLSpartan04]

If your truck had spray in liner, it's possible the connectors for the output panel in the bed might not be seated sufficiently, IIRC they remove the panel when doing the liner install, then restore it once the coating has cured, other members have experienced it being completely disconnected.

Thanks, I do have the factory spray in liner, I will check that!

 

[FLSpartan04]

You probably have a loose ground somewhere in the truck. You could try to find it, or let the dealer do it for you.

Yes, I will take a look at the output panel connectors per @TaxmanHog , if there is nothing obvious, I will let the dealer deal with it when I have time.

 

[FLSpartan04]

Nothing really seemed out of sorts, but i didn’t want to break the seal on the panel box. I don’t think they would have done that either when doing the spray in. Everything looked ok underneath as well.

 

[PreservedSwine]

Tracing ground faults can be quite tedious. Does your pro power trip when simply energized and not under load?
Even if one truck works and the other doesn’t, if you want to go deep into the weeds, it doesn’t necessarily mean the issue isn’t with the load. A gfci will trip at roughly 5ma of current leakage. But sometimes there can be very small discrepancies between gfci,’s. If you’re leaking, say 4.9ma, one gfci may trip and another may not.
Before pointing that finger at the truck, it wouldn’t be a bad idea to try a simpler test with the circuit in question.

 

[flyct]

Tracing ground faults can be quite tedious. Does your pro power trip when simply energized and not under load?
Even if one truck works and the other doesn’t, if you want to go deep into the weeds, it doesn’t necessarily mean the issue isn’t with the load. A gfci will trip at roughly 5ma of current leakage. But sometimes there can be very small discrepancies between gfci,’s. If you’re leaking, say 4.9ma, one gfci may trip and another may not.
Before pointing that finger at the truck, it wouldn’t be a bad idea to try a simpler test with the circuit in question.

Could the truck sense a load ground fault with the ground disconnected from the truck output to the house?

I was there today. With his truck It trips immediately as soon as any home 120v load enabled. With my truck everything worked great. We even were able to run one of his 2 home central air conditioners with my truck. It was drawing around 900 watts per leg.

He ordered a splitter that converts the 240v output to 2 separate 120v legs. Once he gets it he can connect a load to each leg individually and see it it trips.

 

[PreservedSwine]

Could the truck sense a load ground fault with the ground disconnected from the truck output to the house?

Yes, but the load would have to be grounded somewhere else (assuming 240v)

On 120vGFCI ground doesn’t matter- the neutral must be carrying the same amps as the hot wire, or the gfci will detect that as a ground fault.

If it’s tripping with anything 120v- if the current isn’t completing the circuit via the truck neutral, and is using another neutral, the gfci will detect that as current leakage and trip instantly.
Before looking for problems that may or may not exist, I suggest just try something simple with his pro-power, not his house, or house circuitry, just to confirm it works or doesn’t work before moving forward.
good luck!

 

[kss1dvr]

If your truck had spray in liner, it's possible the connectors for the output panel in the bed might not be seated sufficiently, IIRC they remove the panel when doing the liner install, then restore it once the coating has cured, other members have experienced it being completely disconnected.

Eureka moment.

I found the 2 connectors feeding the PPO panel disconnected and could not figure out how that would have happened. Spray in liner was done right after the truck was purchased and mystery is now solved.

 

[flyct]

ground

......................................Before looking for problems that may or may not exist, I suggest just try something simple with his pro-power, not his house, or house circuitry, just to confirm it works or doesn’t work before moving forward.
good luck!

That is why I suggested the NEMA L14-30P Male to 5-15R splitter to independently test each 120v leg of the 30a/240v outlet with a load on it . If it trips with a 120v load plugged it to the adapter that would confirm the truck is the issue and give the dealer something to repeatedly verify a fault.

 

[FLSpartan04]

Yes, but the load would have to be grounded somewhere else (assuming 240v)

On 120vGFCI ground doesn’t matter- the neutral must be carrying the same amps as the hot wire, or the gfci will detect that as a ground fault.

If it’s tripping with anything 120v- if the current isn’t completing the circuit via the truck neutral, and is using another neutral, the gfci will detect that as current leakage and trip instantly.
Before looking for problems that may or may not exist, I suggest just try something simple with his pro-power, not his house, or house circuitry, just to confirm it works or doesn’t work before moving forward.
good luck!

To confirm, I went out there with a vacuum and hammer drill, and plugged each into one of the 120v receptacles in the bed (I believe each one is tied to a leg) and ran them simultaneously without tripping the pro power GFCI. Something about the 240V connection to the house load it doesn’t like. To be clear, I was testing by plugging into the L14-30R and turning on the interlock breaker. No trip. Then the first breaker I turn on (usually chose a 120 breaker that supplied a single receptacle in my garage with a work light on it), would cause the pro power gfci to trip. I have two cables coming tomorrow to narrow my issue. I have a 240v to split 120v to try the same test (run a vacuum and some other loads) to see if it trips off the 240. I also bought a y cable to make the two 120 loads into a l14-30r to see if the test through the interlock breaker still trips. I am thinking I can narrow down if there is a bad connection at the 240v outlet if it works with the y cable. Otherwise, maybe there is a grounding issue with the truck. Not sure. I’ll report my findings when I get the cables (and some time). Thanks all for the assistance!

 

[FLSpartan04]

Gotta love Amazon overnight delivery. The first of two cables came and I was able to test combining the two 120 legs with a y adapter and same result. Turning off main and all breakers first. Then turn on interlocked feedback breaker with pro power in. All is fine. Next turn on a single 120 breaker that powers a single gfci receptacle in the garage (I unplugged all loads from the receptacle). As soon as the breaker turns on, the pro power gfci trips.
This confirms it is not a specific problem with my 240 outlet on the truck.
So now I hope my second test with the other cable (240 to 120 loads) will cause a trip. I need to be able to “prove” my problem without bringing my house to the dealer.

 

[FLSpartan04]

Good news! @flyct had one more idea to try. Unplugging the truck from the charger. I subscribe to the ABC (always be charging) philosophy. It didn’t occur to me that the ground would have another path through the Ford Charge Station Pro back to the truck. I tried it again (to the chagrin of my family who is sick of me cutting the power) with the CCS plug out, and it worked! Hopefully, this can help someone else in the future. I am actually glad I had the issue, as I now I know to unplug the truck in a power outage scenario to provide home backup power through pro power. If I didn’t have it plugged in for my test, and had it plugged in during a real power outage scenario, I would have been far more frustrated!
Thanks all, especially @flyct, for the help!

 

[flyct]

It was a pleasure meeting you and I’m glad we figured it out

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