First time buying an inverter generator

[Richard Grotto]

Or any generator for that matter. So I will be using it for powering my A/C for my TD it is 5000 BTU and probably a small TV and to charge a couple cell phones (all at night).
So do I need to ground it to my trailer, use a grounding rod or none of the above?

[MickinOz]

Difficult question to answer.
Some general points:
Read the amperage required by your AC.
Read the amperage supplied by your proposed generator. Probably needs to be at least three times AC amps to cater for start up current.
Read the manual of your proposed generator, it may actually offer advice on grounding. Mine does.

Some sort of grounding wire will be required if you want to run residual current device. (Used to be called an earth leakage circuit breaker.)
This is why electricians are worth paying.

[saltydawg]

My answer will not answer your question. I am a master electrician.

NEC dictates that trailers do need the frame to be grounded, but do not bond the neutral and ground. This is done as the main and only main point of disconnect. which in a house is the main panel. Trailers as far as the nec states are mobile homes, our tear drops are not mobile homes. So the nec does not really cover us. There is stuff on portable generators but its more meant for big ones like what is used to run building during construction.

The other issue is an electric theory problem power has to return to its point of origin. IE it is generated at the power station, every electron generated returns to that generator even ones that go to ground in shorts. this is obviously strange when talk about portable generators. So a ground rod by theory will do nothing.

What mick talks about for the earth leakage CB is what we call a gfci.

My opinion is yes you connect the ground from the cord to the generator to the frame, but you must make sure it is also connected at the generator side ( ie do not break off the ground pin on the cord ). Then you have to have a gfi either in the generator or one of the one built into a or on the cord itself. Connecting to frame only really serves one purpose, if there is a short, for it to be a short it would have to connect to the frame. Otherwise its not a short its just energizing the frame, thats why it needs to go back to the generator on the ground so it can be sensed and trip as a short.

A gfi built in will detect the short and shut off faster than the generator can trip on the short ( unless the generator has the gfi ) .

are you confused yet.

Also multiple gfis are not a bad idea either.

https://www.homedepot.com/p/Leviton-15- ... /301971300

[Richard Grotto]

So then run the ground wire (the generator had a screw dedicated to this) to the frame of the trailer?

[saltydawg]

So then run the ground wire (the generator had a screw dedicated to this) to the frame of the trailer?

The cord you use should be fine.

just make sure you run a wire from the plug ground connection on the trailer to frame.

btw all this assumes your wiring the trailer for power if your just using cords dont worry about it.

[Richard Grotto]

So then run the ground wire (the generator had a screw dedicated to this) to the frame of the trailer?

The cord you use should be fine.

just make sure you run a wire from the plug ground connection on the trailer to frame.

btw all this assumes your wiring the trailer for power if your just using cords don't worry about it.

well the trailer has the A/C for "shore power" and I have a battery for the interior lights.

[saltydawg]

So it has installed shore power wiring? then run a ground to the metal frame.

[Richard Grotto]

ok, sounds good, thanks.

[usmc70_14]

Soooo now I'm confused with my build .. Not to hijack the thread but this is what I'm doing...


4 outlets in trailer leading to breaker panel. White wires go on the stock bus bar inside . In braaker box, I have installed a serperate bus bar that all of the 4 (outlets) grounds go to. That bus bar is then grounded to a screw on the outside of the box, to the trailer. Making sure I've removed the paint on the frame.

Am I wrong or this is correct?


Sent from my SM-G955U1 using Tapatalk

[saltydawg]

Soooo now I'm confused with my build .. Not to hijack the thread but this is what I'm doing...


4 outlets in trailer leading to breaker panel. White wires go on the stock bus bar inside . In braaker box, I have installed a serperate bus bar that all of the 4 (outlets) grounds go to. That bus bar is then grounded to a screw on the outside of the box, to the trailer. Making sure I've removed the paint on the frame.

Am I wrong or this is correct?


Sent from my SM-G955U1 using Tapatalk

nope thats perfect, exactly how I would have done it.

[Richard Grotto]

would this also work If I ran a wire from the negative of the battery to the frame?

[saltydawg]

would this also work If I ran a wire from the negative of the battery to the frame?

Yes you can mix, remember the 120v ground is only for shorts it does not normally have power on it. And you do want a gfci on the cord or wired in so if there is a problem is shuts off very fast.

[Richard Grotto]

The camper has a surge protector/power strip, I figure this will suffice?

[MickinOz]

do need the frame to be grounded, but do not bond the neutral and ground.

Seems about the same as would be done in Oz.
Generators can be a special case depending on whether the AC is "floating" or has one side tied to the ground pin.
But my electrical son tells me that any bonding between neutral and ground must be up stream of the RCD/ELCB/GFCI and if the earth and neutral were bonded at the trailer the RCD back at the generator would not work as intended.
At least, I think that's what he said.
Wiring rules here don't specifically require generators under a certain size (25 KW?) to be earth staked.

[saltydawg]

But my electrical son tells me that any bonding between neutral and ground must be up stream of the RCD/ELCB/GFCI and if the earth and neutral were bonded at the trailer the RCD back at the generator would not work as intended.
At least, I think that's what he said.

if RCD means GFI then he is correct. if fact it should cause it trip or worse energize the frame with the neutral load.