Generator tripping.

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ram11379

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I am currently installing a generator for a customers home. I did this the same way I do all my generators. I put in a sub panel next to the main, installed a 30 amp 2 pole breaker in the main panel and ran a line from the main panel to the generator panel. Then connected that feed to a 30 amp breaker and ran the lines that were to be run off the generator to the generator panel. Then I ran the generator feed into another 30 amp breaker in the generator panel and installed the Square D lock between the two 30 amp breakers that only allows one to be on at a time.

The problem is though on this job the customer has a eb6500 Honda generator. That particular generator is GFCI protected and the kicker is that the neutral is bonded to the frame. So when I turn the power on for the generator the Generator GFCI kicks immediatly Even with no load.

I believe this is happening because the neutral is boded to the generator frame. Obviously the neutrals and the grounds in the home main panel are bonded. My only conclusion on options I can think of would be to find where the netral is bonded to the frame of the generator and dissconect it.

Anyone come across anything like this or have any input to help with this situation? Also why would the neutral be bonded to the frame if this would cause this problem on any residential application? I'm looking forward to the input, thanks.

Mike
 
I believe this is happening

I believe this is happening

It could be the house wiring, the gen wiring, or some interaction between them.

Ask Honda about this, or
draw a schematic of the entire setup and trace the current flow that is causing the trip, to your satisfaction.

A "conventional" GF that works properly only knows the difference between what goes out on the L line and what comes back on the N line, over ~4 mA. It assumes the missing current is off somewhere shocking someone. Some of this leakage current may be reactive.

Before you start making irreversible mods, ask if there is any other possible explanation, no matter how farfetched, for what you're seeing.
 
The problem is though on this job the customer has a eb6500 Honda generator. That particular generator is GFCI protected and the kicker is that the neutral is bonded to the frame. So when I turn the power on for the generator the Generator GFCI kicks immediately Even with no load.
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The neutral comes connected to the frame. It is normally used with extension cords. Is it connected permanently to the house wiring? I assume you do not have a transfer switch?
 
He has set up a parallel path EGC and grounded conductor, current travels both paths trips GFCI. Isolate the grounded conductor at the genset.
 
GF that works properly

GF that works properly

Four possibilities:

Trips w/leakage current
no trip w/leakage current
trips w/no leakage current
no trip w/no leakage current

The test button takes care of the first two.
The first and last is normal.
The third one might be a possibility here, and could be checked with a meter.
 
bob said:
The neutral comes connected to the frame. It is normally used with extension cords. Is it connected permanently to the house wiring? I assume you do not have a transfer switch?
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Yes it says right on the frame that neutral is bonded to frame. For what reason I don't know. Yes I am running a 10/4 so cord with four prong twist locks on both ends. It is not permanently connected as it is four a company that owns multiple residences for helping the handicaped. This is a small organization so they are wanting all there homes setup for a mobile generator that can be taken around if there is an outage just long enough to keep them heated.

I do not have a transfer switch just two breakers in a sub generator panel with a feedback lockout switch between them. I have read up a little and it seems this is a problem for these types of generators in residential applications. The only solution I have seen found though is removing the bond between the frame and neutral. This I believe is not Osha approved though.
 
brian john said:
He has set up a parallel path EGC and grounded conductor, current travels both paths trips GFCI. Isolate the grounded conductor at the genset.
Click to expand...

Yes that is what I believe, but the question is what to do safely. Or am I going to be forced to go back to this non-profit organization and tell them they need a new generator that doesn't have a neutral bonded to the frame?
 
080507-2121 EST

Contact the Honda dealer and they will tell you where the jumper is to remove.

I believe then you will be grounding the Honda frame thru the EGC in the 4 prong plug to the house EGC.

Logically this says you should have the generator shut down when inserting or removing the twist lock plug.

Someone else will have to tell you how this relates to code.

.
 
ram11379 said:
Yes that is what I believe, but the question is what to do safely. Or am I going to be forced to go back to this non-profit organization and tell them they need a new generator that doesn't have a neutral bonded to the frame?
Click to expand...
Check this post. It has about the same information as your post.

http://forums.mikeholt.com/showthread.php?t=97685&highlight=generators

Check the Honda Bulletin which is attached.
 
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Thanks Gar I am going to contact Honda. Thank you to Bob I searched and somehow didn't find that post. It is exactly what I needed.
 
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