So years ago my ex brother in law wired in a generator inlet for us. I've never used it and was looking to make sure its usable.  Its a 14l-30p 4 wire, neutral, ground and two hots. He wired it into a double 30 amp breaker with three wires, using the ground and the two hot terminals and left the neutral hanging. Will this work and is it safe?  Thanks,

No, and no

That neutral should be hooked to the neutral bar.

You also need an interlock kit installed so that the gen breaker and the main breaker CAN NOT POSSIBLY be on at the same time.

This.   All of it.  

When I was running an 8KW generator that is how I had it wired.   I used 10 gauge wire that was about twenty feet long, connected the two hot wires (L1 and L2) on the double pole 30 amp breaker, the neutral wire was connected to the neutral bar of the panel and the ground wire to the ground bar of the panel.   I ran many days with that arrangement.   I did not have a manual interlock and I paid very close attention to what I was doing when switching to and from generator power but I have formal training on electricity, generators, and wiring.    The cords for the generator were locked up to prevent anyone else from hooking them up.   Now I have a transfer switch and it is a much safer arrangement.  

Do it correctly otherwise you can kill people.

Yes I am ripping it out and having it done by a professional electrician with an interlock, etc. I am just curious why he did it that way, what was he trying to do?

I wouldn’t rip it out yet.   I would have a qualified electrician look at it first.   It may be as simple as relocating the breaker in your panel, hook up the neutral, and install the interlock.   That would be significantly cheaper than having the electrician running it all.

This isn't hard. You don't need to rip anything out. Do a little reading, get a lockout plate and 2 pole cb, hook up neutral and just verify the terminations.

There are tons of online guides and pictures.

This and this

Based on your description of shoddy work, I'd also verify it's wired with 10AWG wire.

ASSUMING that it is 10AWG wire and his connections are solid then it SHOULD work.   But if you had any GFCI's involved then they wouldn't work.   Or if anything went wrong then it would be bad.    Basically he was using the ground and neutral on the same wire.   This is how things were done in the 1950's era but standards have changed since then and things are much safer now.  

To be honest though, most people don't properly ground their generators anyways so it depends on where you draw the line on "much safer now".

If you're using a generator as a portable (hooking extension cord to the generator) the ground & neutral should be bonded in the generator. If you're backfeeding a panel you should unbond the ground & neutral at the generator, drive a ground rod, and bond the ground to the rod. Rarely does anybody do that when hooking the portable up to be a stationary genny. I don't, it's not compatible with how I use my generators because sometimes I use them both ways at the same time, back feeding the house panel but also using extension cords for a few things in the garage (on a different panel).

With the ground/neutral bonded at 2 places the ground will carry current. Thus it's no different than OPs setup where the ground is carrying all the neutral current. Just be cautious that grounds are sometimes smaller than the other conductors in wire & cords so it may not be able to handle max output w/ an unbalanced load before the cord starts to melt.

Lastly, I believe the GFCIs would still work because they are looking at the current on their individual circuit, not on the supply side of the panel.

You have that backwards.

The generator is grounded via the four wire inlet when backfeeding.
You wouldn't take the cover off the panel and unbound the ground and neutral bases.
If you didn't have the wires segregated by bus this would be bad anyway.
The ground and neutral shouldn't be bonded in a portable generator.

The grounding screw on a generator is for use when it's being used as a portable generator with an extension cord.
In that configuration the ground is floating, there's no safety path to ground.

Most portable generators are not "separately derived systems".

SigOwner is correct.   But no, I don’t go through the proper mechanisms either.   I rely on the panel connection for the Neutral-Ground Bond.    I also rely on the panel ground rather than drive a ground rod for the generator.

Here is the diagram for my Champion generator.  The ground and neutral are bonded internally, from the factory. *

*nope  

Attached File

FWIW, I'm not talking about unbonding the G/N busses in the panel, I'm talking about at the generator. Portable generators are usually shipped with them internally bonded. To connect a portable to a home backfeeding through a panel "properly" they need to be unbonded. That is only when backfeeding, when using extension cords they should be bonded. I believe the reason is that they become separately derived systems in the backfeeding role, but the fine folks over at Mike Holt forum know much more than I do about the actual code definitions and I'm just repeating what I've learned over there.

Because the generator is bonded and the panel is bonded, using a 4-wire cord is nearly useless because both the ground and neutral conductors will then share the neutral current, each carrying a portion of it. Thus, OP's situation, assuming the ground conductor size throughout (including internal to the genny) is appropriate, isn't anymore dangerous or "wrong" than how most of us use our portable generators as stationary units.

My understanding is that if the designers expect the generator to be wired into a panel then they will not connect the neutral and ground inside the generator.   If they expect the generator to power extension cords then they will connect the neutral and ground inside the generator.   Since any generator can go either way then there is a strong possibility that it end up being wrong.  Personally, I would rather have two neutral/ground bonds than zero neutral/ground bonds.  FYI:  Zero is bad.   I have heard of problems caused by multiple neutral/ground bonds but I have never seen one and do not personally know of anyone that has.   My understanding is that this issue is typically caused by the connections being hundreds of feet apart.   Not common for most home generator installs.  

There should only be one neutral/ground bond in power distribution system so if your generator is wired that way then technically you should either break that bond when wiring into a panel or you should break the bond in the panel.   Again, another reason to consult a qualified electrician.   They can ensure that the generator/panel are configured to work properly together.  

That brings up an interesting question.   How many generators are wired like that?   I know that a lot of generators are not because the designers expect them to be wired into a panel.   I know that my 8KW is not.   I know that my 20KW is not.   I don't know about my 2KW and 2.2KW.   I should check.  

We had a thread on here a while back where a member built his own "furnace transfer switch" with a double pole double throw switch and an male plug to allow him to easily run his furnace off a generator extension cord.   When he tested it the furnace wouldn't run.   He had to make a neutral/ground bonding plug for his generator and then it worked.   I have seen stuff like this before.  

Complications like this are what stops me from saying "this is easy" and it pushes me to advise people to contact a qualified electrician for generator/panel connections.  

But again, OP your install has issues.   But it may be much cheaper/faster to leave it and have a qualified electrician fix it than tear the whole thing apart and pay the electrician to put it all back in with slightly different connections when they are done.

My Honda generators are not bonded internally.  I tried hooking them up to my Tesla charge cord and it showed ground fault-missing.  I bonded the neutral and ground on the generator with a piece of wire and it works normally now.
I'm looking forward to the day when I take the generator with me and stop on the side of the freeway and hook it up.  Should get a few lookers.

Assuming that you are using 15 amps or less then you can buy a plug like this:



and just connect a fourteen gauge wire from the ground (green) to the neutral (silver).    Then when you need the generator bonded you plug it in.   When you don't want it bonded then unplug it.   But make sure that you get the right two terminals.   if you jump gold to silver or gold to green then you won't like what happens when you plug it in.  

Care to circle the bonding point?  I'm not seeing it.

My Harbor Freight open frame 240V genny is bonded internally.

None of my 120V inverter generators (from 3 different manufacturers including Honda) are.

This

Damn, you're right.  My eyes are old.  

Not a problem.



I just checked all of mine with a continuity tester.
I was suprpised the big one was bonded.
I rarely use that one, but almost always use it feeding my panel, so I'll need to pull the bonding wire.  Thanks.

Question for you. Does the main breaker isolate the neutral from the pole?

I've read it does not and thus should not be hooked up.

Isn't there a scenario where current could sink through the neutral to the pole?

Thanks for the help. So he used a 30 amp dp breaker but it is at the bottom of the panel, so I assume it would need to be moved to the top to use an interlock? Assuming he used correct guage wire, and everything else os ok, would I move the breaker, run a neutral to the inlet and then install the interlock? I appreciate the help links to any diagrams would help, thanks. My current generatoris a 5000w coleman open frame, i'm getting a champion 2500 inverter and may eventually get another and a parallel kit.

Edit to add he did use 10 guage wire to run from the inlet to the panel.

1. Absolutely not.

2. That is completely wrong.

3. No, neutral is ground in the utility world.
In the utility world, it’s not dead unless it is grounded.

There may be better places to purchase a kit depending on what brand your panel is, but start your research here.

https://www.interlockkit.com/Default.asp

If a home lost it's ground (losing it's bonded neutral), while backfeeding with a generator, could the neutral sink back to the pole?

Ebay has a good selection as well, some listed and some not listed.

The one for my panel was less than half the price of what that site wants. Just as a point of reference.

Ok, so thanks to everyone who helped, I know what I have to do, just a couple more questions.

I will reposition the breaker so an interlock can be installed.

I will run a 10 gauge neutral line from inlet to box neutral bar, this is in the basement, overhead, do I need to use conduit?


There are adapters to step down the inlet to a standard 110 volt plug-i assume no issues if I used one with the 2500 watt inverter once everything is sorted out ?