# Bonded neutral generator needs to be floating neutral?



## toddlaroche (Jun 19, 2020)

> I’m using a DuroMax12000EH Generator as a power back-up to my house for when the grid goes down. I’m feeding power from the generator directly into my house breaker panel (with an approved interlock device) from the generator’s 50amp 240volt receptacle. The two hot leads go directly into a bipole 50amp breaker on the panel, and the neutral and ground wires go (unswitched) directly into the respective neutral and ground busses in the panel. Because it is my house’s primary panel, the neutral and ground busses are connected together.
> Because there is a grounding circuit established between the generator and ground at the panel with this particular set-up, it is redundant, and problematic, to ground the generator itself to a grounding rod as well. Further, it would be prudent to eliminate the possibility of grounding the generator through the frame via a circuit made by a human body!
> Based on my review (captured in the picture below and verified by continuity testing between neutrals and grounds in each of the receptacles) my generator’s neutral and ground circuits are bonded to the frame.





> Given this, I believe it would be prudent to convert the generator from a bonded neutral to a floating neutral configuration by disconnecting the short jumper wire that grounds the neutral (white wire) coming out of the windings to the generator casing. Check out the attached photo to confirm I’m doing the right thing.





> I’m trying to be as safe/careful as possible!
> 
> Thanks for your guidance.


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## motormonkey (Jul 10, 2016)

Yes, you should remove that jumper between the ground (frame of the generator) and neutral. Save the jumper. If you ever need to operate the generator independently from your house wiring you'll want to re-install it.


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## toddlaroche (Jun 19, 2020)

motormonkey said:


> Yes, you should remove that jumper between the ground (frame of the generator) and neutral. Save the jumper. If you ever need to operate the generator independently from your house wiring you'll want to re-install it.


Motor monkey, thank you for your clear response/explanation to my other question about bonded neutrals and for responding to this question. I trust your judgement on this; it’s what I’ve been thinking all along, but I’m not an electrician. I do know that “experts” may tell you never to meddle with the wiring in a generator and/or that removing the ground-to-neutral jumper isn’t good to do and would void any warranty, but I’d rather be safe than “correct”!! Thanks for taking the time to read my questions and respond to them; much appreciated!!


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## ToolLover (Jan 13, 2020)

GFI's do not work well with joined neutral and grounds. If you have GFI's you should separate them.


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## tabora (Sep 6, 2018)

toddlaroche said:


> Motor monkey, thank you for your clear response/explanation to my other question about bonded neutrals and for responding to this question. I trust your judgement on this; it’s what I’ve been thinking all along, but I’m not an electrician. I do know that “experts” may tell you never to meddle with the wiring in a generator and/or that removing the ground-to-neutral jumper isn’t good to do and would void any warranty, but I’d rather be safe than “correct”!! Thanks for taking the time to read my questions and respond to them; much appreciated!!


What @motormonkey said to do is exactly correct. It should not void any warranty. The jumper is placed there to allow easy swapping between the two operational modes of your generator.


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## KRE (Nov 29, 2011)

ToolLover said:


> GFI's do not work well with joined neutral and grounds. If you have GFI's you should separate them.


Enlighten me as to why you believe that.

All
I suggest some of you ohm between neutral an ground on your genset, then think about the readings you get, and why it reads like it does.


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## ToolLover (Jan 13, 2020)

KRE wrote: Enlighten me as to why you believe that.
My house was built in the mid 50's.
4-0 SEC was used between the meter and the main.
If you know about SEC, then you know the neutral is woven around the two feeds.
My neutral touches the cable clamp where the SEC enters the main and it is clamped securely at that point to the breaker box, adding a ground to the box puts them together.
This arrangement creates a problem for GFI's in that panel.

Now I want to add what I experienced with a garage wiring install:
Code requires that outside receptacles be connected to a GFI device.
So I ordered a 50 amp GFI breaker.
I set about to wire the garage, not thinking I wired a jumper from the neutral to the ground bus.
After I powered up the garage, I thought I had a bad 50 amp breaker as it tripped every time I tried to reset it.
When the inspector arrived he pointed to the bond and asked why I did that. I was embarrassed to no end and quickly removed it. He said to me "You have been out of the loop too long!" but he passed the install anyway.
You need to experience an embarrassing situation to understand "WHY!"


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## KRE (Nov 29, 2011)

ToolLover said:


> KRE wrote: Enlighten me as to why you believe that.
> My house was built in the mid 50's.
> 4-0 SEC was used between the meter and the main.
> If you know about SEC, then you know the neutral is woven around the two feeds.
> ...


Do you really understand how a GFI works?


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## ToolLover (Jan 13, 2020)

Simple: any slight trickle of current to the ground causes a trip.
Now, that being said, if the neutral and ground are tied together, how can the GFI sense a current flow to ground????
I assume you have a different idea of how a GFI processes the fault.


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## KRE (Nov 29, 2011)

ToolLover said:


> Simple: any slight trickle of current to the ground causes a trip.
> Now, that being said, if the neutral and ground are tied together, how can the GFI sense a current flow to ground????
> I assume you have a different idea of how a GFI processes the fault.


I suggest you really learn how a GFCI is wired, an operates, then rethink you answer above.


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## ToolLover (Jan 13, 2020)

The *GFCI* will “sense” the difference in the amount of electricity flowing into the circuit to that flowing out, even in amounts of current as small as 4 or 5 milliamps. The *GFCI* reacts quickly (less than one-tenth of a second) to trip or shut off the circuit.
Now with that being said, There is only one path to unbalance the circuit, and that is for current to go to the ground.
Is that why the NEC requires GFCI's on outside outlets? To detect a fault going to ground or going to ground thru your body to ground.
Of course I guess you have a different definition. Enlighten me please.


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## KRE (Nov 29, 2011)

ToolLover said:


> The *GFCI* will “sense” the difference in the amount of electricity flowing into the circuit to that flowing out, even in amounts of current as small as 4 or 5 milliamps. The *GFCI* reacts quickly (less than one-tenth of a second) to trip or shut off the circuit.


Really? Explain how then, it still allows power to flow when powering a shifty resistor?


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## ToolLover (Jan 13, 2020)

I expected an answer to my question, "Your definition of how it works" not another question tied to electronics.
My experience with electronics and shifty resistors:
First "shifty resistor"!
I have a Fischer Paykel washer that has 38 volts AC to ground.
The idiots that designed the electronics tied a smoothing resistor to ground instead of to the neurtal.
The washer will not trip the GFCI either, but that is electronics for you.
Note: I went round and round with FP and they refused to resolve the issue.


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## KRE (Nov 29, 2011)

ToolLover said:


> I expected an answer to my question, "Your definition of how it works" not another question tied to electronics.


It's not about my definition at all, it's about how a GFCI works, compared to how most people think it works. Handing someone the answer does not inspire one to seek the truth, or gain knowledge. 45+ years in the EPG field plus 10+ years of teaching instruction has taught me one thing. When people have to do their own research or experiments they retain that knowledge. One issue with forums is the amount of misinformation that goes unchecked. Unchecked incorrect information soon becomes fact. Incorrect facts, lead people down rabbit holes for no reason.


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## toddlaroche (Jun 19, 2020)

KRE: Are you saying that MotorMonkey and ToolLover gave me bad advice?!?


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## ToolLover (Jan 13, 2020)

@Todddlaroche: Did you see an answer to the question from KRE?
All I saw was KRE side stepped the question again.
You can Google the question and will find the same answer that I offered in #9 & #11 posts.
You do what you want.


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## KRE (Nov 29, 2011)

ToolLover said:


> @Todddlaroche: Did you see an answer to the question from KRE?
> All I saw was KRE side stepped the question again.
> You can Google the question and will find the same answer that I offered in #9 & #11 posts.
> You do what you want.


Laughing, I gave you an answer you just what everything handed to you, like most people these days. You think you know more than you do, and I assure you, and your googled answer is wrong. If you think I'm going to tell you the correct answer don't hold your breath.
Tell you what, I've had about a belly full of guys like you trying to be something your not nor will never be, giving bad advice that one day will get someone hurt. You do as you wish, I'm done with this place.


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## ToolLover (Jan 13, 2020)

OOH! Has the professor left the room?


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## motormonkey (Jul 10, 2016)

A bit of a deviation from the OP, but just to clear up a point about GFCI.

Neutral is the current return path for any 120 volt circuit. If you measure the current on the neutral, it should be exactly the same (or very close) as the current on the hot conductor. In a ground fault situation, some of the current from the hot conductor will have found its return path through some path other than the neutral. (like to ground if someone or something in contact with the ground should come into contact with the hot conductor.) A ground fault circuit interrupter compares the current on the hot conductor with the current on the neutral. If there is less current on the neutral than on the hot conductor, it trips. It works independently of the ground conductor altogether.


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## Melson (Dec 8, 2019)

Problem with some people is he never left the classroom, just want to preach theory and have no clue about how stuff works in the real world. 
To actually *fix something in the field took a different approach (skill set?) than what I learned school.


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## motormonkey (Jul 10, 2016)

Let's let this go or I'll close the thread.


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## crabjoe (Apr 20, 2020)

ToolLover said:


> GFI's do not work well with joined neutral and grounds. If you have GFI's you should separate them.


Before I picked up my B&S Q6500, I was really worried about GFIs tripping when connected to the house. What I found was that with the Q6500, I'm not having any issues with the GFI, so I'm leaving well enough alone.. That is, unless someone can give me a good reason why I should, even though everything works fine as is.


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## iowagold (Jan 22, 2020)

crabjoe said:


> Before I picked up my B&S Q6500, I was really worried about GFIs tripping when connected to the house. What I found was that with the Q6500, I'm not having any issues with the GFI, so I'm leaving well enough alone.. That is, unless someone can give me a good reason why I should, even though everything works fine as is.


are you using the twist lock joe for your generator inlet connection?


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## crabjoe (Apr 20, 2020)

iowagold said:


> are you using the twist lock joe for your generator inlet connection?


Yes, I'm using the twist lock. I even tried connecting a heat gun to the 120v outlet while I had the 240v twist lock connected to the house service panel and I didn't have any GFIs trip.. not in the house or the generator.


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