Portable generator bonding

[sparkync]

If a portable generator is used as a "stand by" generator for a residential house, does the neutral have to be separated in the generator? I couldn't find it in the Code reference. Thanks

 

[ActionDave]

The bonding or lifting of the neutral in the generator has to do with the transfer switch being a Separately on Non Separately Derived System. I think it's the 2020 code that began requiring a sign that describes what kind of transfer switch you have.

My personal opinion is that the neutral bonded at a portable generator wired to a NSDS transfer switch isn't that big of a deal as long as it's a rubber insulated cord making the connection, which it almost always is, but it can be a problem if the generator output is GFCI protected.

 

[sparkync]

The problem is that the generator manual says to put on GFCI protection if operated in any damp area, and it will be located outside of course.
So I guess that would answer my question that they should be separated. Thanks

 

[infinity]

The problem is that the generator manual says to put on GFCI protection if operated in any damp area, and it will be located outside of course.
So I guess that would answer my question that they should be separated. Thanks

I removed the neutral bond from my generator since I'm operating as a non-SDS. Very easy task took less than 10 minutes.

 

[goldstar]

I removed the neutral bond from my generator since I'm operating as a non-SDS. Very easy task took less than 10 minutes.

Does the removal of that connection result in voiding of any warranties or failure to follow any manufacturer's recommendations ? Also, did you drive a ground rod ? You know the EI that I'm dealing with up here.

 

[roger]

Does the removal of that connection result in voiding of any warranties or failure to follow any manufacturer's recommendations ? Also, did you drive a ground rod ? You know the EI that I'm dealing with up here.

I remember at least one manufacturers instructions (don't remember which one I think it was Honda) telling the user to make the change and showing how to do it.

 

[goldstar]

This is the unit I'm dealing with :

DuroMax XP13000HXT 10500W/13000W Tri-Fuel Gasoline Propane Natural Gas CO Alert Remote Start Generator New

DuroMax XP13000HXT 10500W/13000W Tri-Fuel Gasoline Propane Natural Gas CO Alert Remote Start Generator New. Authorized Dealer. Free shipping on generators. 3 year warranty.

factorypure.com

Unless I missed it, the instructions don't show how to remove the bonding wire. There is a wiring diagram at the end of the manual. However, it does show that the bond is under the engine cover and they show that in the instruction manual.

 

[infinity]

Does the removal of that connection result in voiding of any warranties or failure to follow any manufacturer's recommendations ? Also, did you drive a ground rod ? You know the EI that I'm dealing with up here.

It likely voids the warranty but I know that on my Generac it can be reinstalled just as easily as it is removed. A ground rod is not required if the neutral is not switched.

 

[LarryFine]

The general rule is that either each of both sources is bonded and you switch the neutral, or the load side is bonded and you don't switch the neutral.

So, you most likely have to configure the stand-by source to match the utility source.

 

[goldstar]

It likely voids the warranty but I know that on my Generac it can be reinstalled just as easily as it is removed. A ground rod is not required if the neutral is not switched.

I'm with you BUT, you know what I'm dealing with up here. It clearly states on page 27 of the instruction manual to "ground the generator to a ground rod or risk the possibility of electrocution." That's all this EI needs to see to fail this installation. I can hardly wait to see what other BS he finds.

 

[tom baker]

I remember at least one manufacturers instructions (don't remember which one I think it was Honda) telling the user to make the change and showing how to do it.

Yes somewhere I have that instruction from Honda. I may be able to post it later

 

[synchro]

I'm with you BUT, you know what I'm dealing with up here. It clearly states on page 27 of the instruction manual to "ground the generator to a ground rod or risk the possibility of electrocution." That's all this EI needs to see to fail this installation. I can hardly wait to see what other BS he finds.

You could argue that the EGC in the cord from the generator connects it to the GES of the home, and therefore it does what the instruction manual is specifying.

 

[shortcircuit2]

Most installation instructions have the statement : "Install according to local codes" or similar. The NEC is adopted in most juridictions and a ground rod is not required if a portable genset is connected to a homes electrical system with a bond at the service disconnect.

To check if a generator is bonded, do a continuity test between the ground and neutral of the receptacle on the genset (while it is off of course). It is "bonded" with continuity between gound and neutral.

It should be an unbonded genset (floating neutral) if connected to a homes electrical system which has a "bond" at the service.

But if you want to use that same portable generator at say a campsite or jobsite, the ground and neutral should be tied at the genset.

I use a male cordcap with a jumper between ground and neutral to make the "bond" by inserting the cordcap into a receptacle on the genset when I use my homes portable (unbonded) backup generator at a jobsite.

 

[goldstar]

Most installation instructions have the statement : "Install according to local codes" or similar. The NEC is adopted in most juridictions and a ground rod is not required if a portable genset is connected to a homes electrical system with a bond at the service disconnect.

To check if a generator is bonded, do a continuity test between the ground and neutral of the receptacle on the genset (while it is off of course). It is "bonded" with continuity between gound and neutral.

It should be an unbonded genset (floating neutral) if connected to a homes electrical system which has a "bond" at the service.

But if you want to use that same portable generator at say a campsite or jobsite, the ground and neutral should be tied at the genset.

This unit will never be used at a remote site. There's no need to do a continuity check from N-G. The schematic in the instruction manual clearly shows a bond between the two. I will have to remove that jumper.

I use a male cordcap with a jumper between ground and neutral to make the "bond" by inserting the cordcap into a receptacle on the genset when I use my homes portable (unbonded) backup generator at a jobsite.

Good info and smart thinking.

 

[sparkync]

Thanks for all the replies. It has helped me determine the correct way to go, but does anyone know the Code reference for it? I'm missing the direct one that says they must be separated. I'm looking in the 2017 code. I see of course where the generator has to be grounded, but am failing to see where the neutral cannot be connected to it, unless we go back to treating it as a "sub panel" sort of thing. I'm still waiting for the generator manufacturer to get back with me on where it's located on their generator. I know I could tear into it, but I don't want to void any warranties.
They're having a problem with it. According to what one rep. said, they're "working" on it. They must have not run into this problem before. It might be manufactured in Canada. I don't know if their standards are the same as ours or not. I have hooked up one brand that Did specify where and how to separate them. Can't remember the brand right now, but anyway, thanks a lot for your input.

 

[LarryFine]

I'm missing the direct one that says they must be separated. I'm looking in the 2017 code. I see of course where the generator has to be grounded, but am failing to see where the neutral cannot be connected to it, unless we go back to treating it as a "sub panel" sort of thing.

How else can you keep neutral current off of the EGC? The sub-panel feeder comparison is valid.

 

[sparkync]

Guess I was confused on definition of "Separately derived system" and "Non-separately derived system". The generator manufacturer sent me a illustration from Mike Holt here, and says that when the neutral is Not switched, it is a "Non-separately derived system" and the neutral and ground have to be separated, and when the neutral IS switched in a transfer switch, it is a "Separately derived system" and does not have to be separated. So when using a "generator inter-lock" bracket, as I'm planning on doing, it is considered a "Non-separately derived system". Sort of confusing, but still looks like in my application, they still need to be separated. Do all agree? Thanks

 

[LarryFine]

See post #9 again.

 

[sparkync]

Ok, thanks Larry. I'll try not to bother again. Think I got it straight now.

 

[goldstar]

Inspector came by and inspected my installation. I had the cover off the wiring compartment and showed him that there was a G-N bonding jumper AND I had installed a ground rod in accordance with manufacturer's instructions and connected it ro the frame of the generator with the lug provided.

He said "leave the jumper in place and remove the wire to the ground rod."

End of story.