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Portable generator neutral bonding

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Mike1903

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I have a basic question and can’t seem to find good answer.

First a background question:
My understanding is that we bond neutral and ground conductors at the panel so that during a ground fault, the current at go back to the source.

Why is neutral bonding to the ground not a requirement for portable generators when they are used in the field? I think it has become a requirement in NEC2020 but curious why it wasn’t before?
Thx!
 
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Mike1903

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larry4406

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My portable generator (Generac) that I bought easily 15 years ago has bonded neutral and ground.

I installed a switch to unbond it when connected to the house.
 
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wyliesdiesels

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Mike1903 said:
I have a basic question and can’t seem to find good answer.

First a background question:
My understanding is that we bond neutral and ground conductors at the panel so that during a ground fault, the current will go back to the source.

Why is neutral bonding to the ground not a requirement for portable generators when they are used in the field? I think it has become a requirement in NEC2020 but curious why it wasn’t before?
Thx!
Click to expand...
no thats not the reason for bonding the neutral. the reason the neutral is bonded is so that breakers will clear fault current, ie. ground fault, on unintended pathways, ie. metal conduit, plumbing etc.

Ummm the neutral is bonded on portable generators so i dont understand your question. The bonding is required so the breakers on the generator trip upon a ground fault.

If you connect your generator to your house, this bond needs to be removed... Hence the reason larry stated that he put a switch on his generator to make this easier when needed....
 
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Mike1903

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wyliesdiesels said:
no thats not the reason for bonding the neutral. the reason the neutral is bonded is so that breakers will clear fault current, ie. ground fault, on unintended pathways, ie. metal conduit, plumbing etc.

Ummm the neutral is bonded on portable generators so i dont understand your question. The bonding is required so the breakers on the generator trip upon a ground fault.

If you connect your generator to your house, this bond needs to be removed... Hence the reason larry stated that he put a switch on his generator to make this easier when needed....
Click to expand...
On the first part, we are saying the same thing. When ground fault occurs, the current will flow on EGC back to the panel and due to bonding, switch to the neutral line and go back to the source and yes, that will also trigger the breaker.

Applying the same logic as bonded neutral in my background question, I would think that portable generators would have always required bonded neutral. Starting with NEC 2020, this became a requirement for portable generators to be listed and my question that why wasn’t this always required?

May be portable generators have always come with bonded neutral and I am just thinking that it is hard requirement with NEC 2020.
 
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jeepxj

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wyliesdiesels said:
Ummm the neutral is bonded on portable generators so i dont understand your question. The bonding is required so the breakers on the generator trip upon a ground fault.
Click to expand...

Bonded to where exactly? maybe i'm missing the term meaning here.

How does this make sense assuming the above means N and G connected. Plug in my tesla to the portable it will error out on a ground fault. put in a bond plug to tie N to G; portable charger works fine on generator.

shows out the logic:
 
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Stuart in MN

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In general, the bond between neutral and ground on a portable generator must be removed if it's used to power a house or other structure that has a ground system in place. On the other hand the bond on the generator is required if the generator used to power something that is portable and not grounded, like if you use it to run a camper or power tools at a job site.
 
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jeepxj

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Stuart in MN said:
In general, the bond between neutral and ground on a portable generator must be removed if it's used to power a house or other structure that has a ground system in place. On the other hand the bond on the generator is required if the generator used to power something that is portable and not grounded, like if you use it to run a camper or power tools at a job site.
Click to expand...

Do consumer grade; portable generators come bonded or not from the factory?
 
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SweetD

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My NorthStar (Northern Tool) generator (Honda engine) came bonded from the factory. I removed the bonding wire so when the generator is connected to the whole-house plug it is bonded to the house system only. I made up a plug to use that bonds the unit to itself should I ever need to use the unit apart from powering the house through the house panel setup (interlock kit). I can plug the plug I made into any of the 120v outlets on the generator and that bonds it. Works great.
 
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wyliesdiesels

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jeepxj said:
Bonded to where exactly? maybe i'm missing the term meaning here.

How does this make sense assuming the above means N and G connected. Plug in my tesla to the portable it will error out on a ground fault. put in a bond plug to tie N to G; portable charger works fine on generator.

shows out the logic:
Click to expand...
when you bond a neutral, it means you connect it to the enclosure and EGC bar in the panel, making them be at the same potential.

This allows breakers to clear ground faults, since a live wire touching a grounded object such as a metallic conduit or motor frame, would create a short between the hot and neutral (at the panel)....

as to your tesla charger situation, it sounds like the generator doesnt have a bonded neutral which the charger requires and you fixed by making a bond plug.
 
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larry4406

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JOE.G said:
Does anyone have a link to a bonding plug? can I rebond ( Hook up ) my neutral to the frame and use the plug on my 8,000W Champion?
Click to expand...
Buy a replacement male 3-prong plug. Connect the neutral and ground together. Nothing else. Use this bonding plug IF you have unbonded the generator’s factory neutral/ground bond AND wish to use the generator as a portable standalone device. If you want to power your home with this generator, then unplug the bonding plug.
 
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JOE.G

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Well ti says I purchased one last February Lol So with this plug I unplug it from the genorator when I have it connected to my home, I then plug it in when I am using the genorator say out in the field or something? I leave the factory Neutral floating/Unhooked from the generator?
 
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AP514

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Pearland, Tx
JOE.G said:
Well ti says I purchased one last February Lol So with this plug I unplug it from the genorator when I have it connected to my home, I then plug it in when I am using the genorator say out in the field or something? I leave the factory Neutral floating/Unhooked from the generator?
Click to expand...
Sounds correct to me.....
 
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