Two generators & Two Panels

Status
Not open for further replies.
Little Bill

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
If you had a 400A/320A service with two 200A panels, and you wanted to power both panels from generator power, could you use an interlock in each panel, along with an inlet for each panel, and have a generator for each panel? I know this can be done, but my question is, will the fact that the neutrals will not be switched be a problem? Assume the generators are unbonded.
 
I feel like i seen this question not to long ago. And that there was now way around objectionable current without switching the neutrals but I could be mistaken.

I thought it was the common connection of the two neutrals and EGC in the separate service disconnects.

I would almost have to draw it out on paper to fully grasp it.

Assuming you have two 200amp service disco and not a single 400.
 
What about one large generator with an isolation transformer to provide an SDS for the 2nd panel? :unsure:
 
hillbilly1 said:
Two separate generators unbonded would not be a problem, with two separate interlocks and inputs.
Click to expand...
There won't be much load on the gennys as they are only 5500W each, so around 22A each panel. I probably wouldn't consider this with bigger gennys. Something just doesn't seem right about the neutrals being able to loop through. I keep thinking one neutral could get overloaded.
 
Little Bill said:
There won't be much load on the gennys as they are only 5500W each, so around 22A each panel. I probably wouldn't consider this with bigger gennys. Something just doesn't seem right about the neutrals being able to loop through. I keep thinking one neutral could get overloaded.
Click to expand...
The current will only circulate in the respective panels, the return path would be back to each of its source, and would not return to the other generator. Unless a hot or neutral is in the wrong panel, with residential, it is extremely unlikely.
 
hillbilly1 said:
The current will only circulate in the respective panels, the return path would be back to each of its source, and would not return to the other generator. Unless a hot or neutral is in the wrong panel, with residential, it is extremely unlikely.
Click to expand...
I can see both panels and nothing is connected from one to the other. All the NM is straight in, so almost impossible for anything to be in the wrong panel. At least a single wire anyway.
 
For the record, this is not for me. If it was, I would just hook it up and see what happens. It is for a customer and I didn't want to do it until I knew it would work.

I know, "retired" and "customer" shouldn't be used in the same sentence!:(
 
Status
Not open for further replies.
Top