Nema 3r surface mount enclosure

O

omega76

Member
Location
California
Occupation
Certified Electrician
Dear Mr Holt,
I am having an issue with a project. The local AHJ keeps failing an inspection.
I'll try to explain for better context.
There is a main panel that some branch circuits were pulled out of. For load relocation.
An outdoor rated box was surface mounted on the outside as it is rated for it. The branch circuits were added to that outdoor box. The holes for those circuits were made on the back of that outdoor rated box. The circuits were then extended into a backup panel switch. This is for a solar battery backup system.
The AHJ keeps failing us. He says that it is not allowed to make holes for wire or conduit entry in the back of a surface mounted enclosure. Only the sides and the top.
I've looked this up in the code. I can not find anything that says that we are in the wrong.
Any information would be greatly appreciated. As I feel like the AHJ is making up his own rules.
 
Romex, branch circuits for this particular. The connectors used are romex connectors. "Two screw connectors" with weather tight sealing washers. But this AHJ says. That no connectors conduit pvc, emt, flex anything. None of it should penetrate the back of the junction box.
 
omega76 said:
Dear Mr Holt,
The AHJ keeps failing us. He says that it is not allowed to make holes for wire or conduit entry in the back of a surface mounted enclosure. Only the sides and the top.
I've looked this up in the code. I can not find anything that says that we are in the wrong.
Any information would be greatly appreciated. As I feel like the AHJ is making up his own rules.
Click to expand...
I'll agree with the AHJ. But not on electrical code, rather on building code.

You'll have no way to seal, and no way to demonstrate that you sealed, the building envelope. Nor could the owner
maintain any such hidden seal. Nor could a future contractor determine if the envelope seal is complete.

----------------
When I see this exact setup on inspections I will call it out and recommend adding trim around the 3R box
to form a rain shield. But that still won't make a proper air, water, vapor or fire seal in a hidden spot behind the box. It's just a patch to make a bad situation tolerable.

That said inspector needs to be able to articulate the failure reason, and maybe yours is bad at it. But the above justification feels supportable on general water resisting code requirements. Perhaps you could quote the exact correction notice.



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Note that "Romex" is not the correct term. That's an obsolete trademarked name for a specific product.
 
brycenesbitt said:
I'll agree with the AHJ. But not on electrical code, rather on building code.

You'll have no way to seal, and no way to demonstrate that you sealed, the building envelope. Nor could the owner
maintain any such hidden seal. Nor could a future contractor determine if the envelope seal is complete.

----------------
When I see this exact setup on inspections I will call it out and recommend adding trim around the 3R box
to form a rain shield. But that still won't make a proper air, water, vapor or fire seal in a hidden spot behind the box. It's just a patch to make a bad situation tolerable.

That said inspector needs to be able to articulate the failure reason, and maybe yours is bad at it. But the above justification feels supportable on general water resisting code requirements. Perhaps you could quote the exact correction notice.



----
Note that "Romex" is not the correct term. That's an obsolete trademarked name for a specific product.
Click to expand...
That is kind of arbitrary. Over the years I have mounted bell boxes, junction boxes, etc. over a hole in the wall. A "back to back" panel installation is very common.
 
I see where you are coming from. This could be an issue that the AHJ has see in the past.
He does not want that in the area he inspects. As he inspects the area frequently.
My apologies, I do know that it is called NM cable, and not romex.
Now, I have done this same process in the past. It has passed inspection. However the inspector did see me patch the hole behind the enclosure, and use sealing washers for the conduit.
That was a different AHJ of course.
 
NM is used all the time. If you mount a surface mounted bell box on a house and come into the back with NM its done all the time everywhere. I don't see anyone transitioning from NM to THWN inside the house before going outside.
 
brycenesbitt said:
Note that "Romex" is not the correct term. That's an obsolete trademarked name for a specific product.
Click to expand...
"Romex™" is a trademarked term, and it is not obsolete. It is in active use by Southwire.
A few years ago this forum got a cease and desist letter from Southwire asking that the forum take measures to make sure the term always appears with the trade mark symbol. Something we could not really so they dropped it
 
don_resqcapt19 said:
"Romex™" is a trademarked term, and it is not obsolete. It is in active use by Southwire.
A few years ago this forum got a cease and desist letter from Southwire asking that the forum take measures to make sure the term always appears with the trade mark symbol. Something we could not really so they dropped it
Click to expand...
They must have been drinking the KoolaidTM
 
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