Request: A concise answer to how to connect Pro Power to a generator inlet

[v2h8484]

Actually, the utility doesn't deliver ground to the house at all, correct? Just two hot wires.

For 120/240V service, the utility provides 2 hots and 1 neutral. My understanding is that the meter collar switch does not connect the truck ground to the house ground so no GFCI faults. I was a bit surprised when I learned it does not violate code since the switch is on the utility service side.

Sponsored

 

[Maquis]

Actually, the utility doesn't deliver ground to the house at all, correct? Just two hot wires. Presumably the meter box is grounded to the panel... thinking while typing, while sitting in a hot tub drinking an IPA.

Definitely don't listen to me!

What I was alluding to is the fact that something in the collar could be doing functionally the same thing as clipping the green wire from the truck.

 

[GDN]

It was aluded to, but I'm not sure anyone has called it out specifically, but those two meter collar/devices are definitely not the same if anyone is confusing them.

PG&E has created one and it is proven to work with the Lightning.

The second is made by Generlink, that will sell to any jurisdiction (but some won't embrace it) and they say it will NOT work with the truck.

So obviously two different approaches and solutions.

 

[Newton]

One thing I will throw out with the caveat that this is something I only vaguely understand (I can wire together boxes following instructions from smarter people) is that it is possible for an automatic transfer switch to destroy an inverter. A well designed switch designed with inverters in mind would be fine, but the possibility is there and I believe that a switch can work fine with a generator and still be bad for inverters. Take this with a grain of salt but I have heard that there be dragons out there...

A good quality 30A automatic marine transfer switch costs around $1000.

Pro Power is an inverter. I'm careful to shut it off before transferring back to utility power even though it should be fine with my generac manual system.

 

[Mmiketa]

These meter base transfer switches were added to the NEC in 2020, and if PG&E is having them installed I would not be questioning its safety. There is no reason to fear monger.

 

[intensifi]

Exactly the time I am concerned with. There are no fuses or breakers upstream of that meter except upstream of the transformer. So if some of those "automatic" circuits inside that sealed metal can fail, the Truck could receive much more amperage/voltage than it would like to see.

California PGE doesn't inspire me that they always follow the safest path...

The cable has protection inline. That is the picture I show with the two reset buttons. This function is also covered in the manual pages I subsequently posted.

 

[Dinozero]

I'm not sure why everyone worries about this as much as they do.

From the two electricians I've talked to in my state, removing the ground from the generator inlet is not a safety concern, the house is still grounded, and the truck is still grounded.

You can find lots of certified electricians on the internet saying the same thing.

https://www.justanswer.com/electrical/b74n2-generator-bonded-neutral-gfci-connected.html

This person here tells the individual to remove the ground from the power inlet, he's a certified electrician with 37 years of experience.


I AM NOT an electrician, and I cannot tell you how to wire your house safely or properly, but I can relay the information that it appears Electricians do not have an issue with this.

This very forum has several members that paid an electrician to come out and look at their generator inlet and the electrician just disconnected the ground in the inlet.

They did state you should place a warning sign next to the inlet, and you should reconnect the ground if you ever sell the house and move.

 

[Pioneer74]

From the two electricians I've talked to in my state, removing the ground from the generator inlet is not a safety concern, the house is still grounded, and the truck is still grounded.

The truck is not grounded. And if you remove the ground from the cord, or from the panel, you have no path for fault current back to the source.

It seems a lot of people don't know the difference between "ground" and "bond".

 

[Dinozero]

The truck is not grounded. And if you remove the ground from the cord, or from the panel, you have no path for fault current back to the source.

It seems a lot of people don't know the difference between "ground" and "bond".

I want to make sure I'm intellectually understanding what you're saying.

The house is still grounded, as if there was any ground fault inside the home the ground that's connected to the main panel box still exist.

The truck is also still a self contained bonded ground set up. It would fault the same way a power tool that did not have a 3 prog connector at the end would fault.

Where exactly would there be "no ground"?

 

[Pioneer74]

I want to make sure I'm intellectually understanding what you're saying.

The house is still grounded, as if there was any ground fault inside the home the ground that's connected to the main panel box still exist.

The truck is also still a self contained bonded ground set up. It would fault the same way a power tool that did not have a 3 prog connector at the end would fault.

Where exactly would there be "no ground"?

Bond and ground are not interchangeable. Your truck has the ground and the neutral bonded together. It in itself is not grounded.

 

[Dinozero]

Bond and ground are not interchangeable. Your truck has the ground and the neutral bonded together. It in itself is not grounded.

Ok. I think I see what you're saying now, but the truck is designed to safely operate in this manner.

If you're out in a field, powering a high current electrical device and it has some sort of malfunction, you're not "more" grounded in that scenario than you would be using the lightning to power your house. I'm not sure the difference?

Also, when disconnecting the ground from the generator inlet, you basically are turning the truck into the "utility company" from a safety/electrical perspective.

The utility company provides 2 hots. The truck would be providing 2 hots.

The main stress here is that you're not adding an additional risk factor to your home beyond the normal utility power.

I do think that if the generator cable experienced some sort of tear or problem and there was a fault on the truck side I'm guessing the protection there would be an internal breaker on the truck would trip. But I'm not 100% sure on that.

 

[Pioneer74]

The main stress here is that you're not adding an additional risk factor to your home beyond the normal utility power.

Maybe. Maybe not. But removing the grounding conductor from the cable you are removing a path back to the truck for fault current to trip the breaker.

 

[Pioneer74]

And, just so people aren't confused, these are the definitions that the NEC uses to define bond and ground.

 

[Dinozero]

And, just so people aren't confused, these are the definitions that the NEC uses to define bond and ground.

Thank you. You have educated me. So the truck is bonded, but it is NOT grounded from the factory.

 

[v2h8484]

I AM NOT an electrician, and I cannot tell you how to wire your house safely or properly, but I can relay the information that it appears Electricians do not have an issue with this.

I agree that it appears that more than few electricians think it's "safe" to disconnect the ground but it's still a code violation. I wonder if these electricians would keep the same opinion if they are responsible for any negative consequences due to the code violation.

Sponsored