How do you enter a surface mounted outdoor cabinet from inside a wall?

M

marmathsen

Senior Member
Location
Seattle, Washington ...ish
Occupation
Electrical Contractor
We're working on a DADU where we are wiring everything with NM cable and using an exterior surface mounted meter/main with distribution. What is a compliant way to enter the enclosure with ~22 circuits? I just read through this thread, I'm not sure there's a great option. The cabinet has two 2.5" KOs, so what I want to do is use a 2.5" PVC TA, staple within 12", run most of the cables through the TA, and duct seal it, but it seems pretty clear that's a violation. I like the idea of a TA because then waterproofing the penetration seems more ideal since it extends past the building envelope. I also found this Wire Waffle from Rack-a-Tiers which seems like it would work but then waterproofing seems hard. I could swiss cheese the back with a bunch of field cut KOs, but again, waterproofing.

Curious what others think the best method would be for cable entry and how do you picture water proofing. Is there a better method than building up a fat ring of sealant (silicone? duct seal?) around the penetrations through the wall and then squish them down as I mount the cabinet? Maybe just seal the gap around the back edge of the cabinet after it's mounted and call it a day (although does that defeat the pupose of the 1/4 gap)?

As always, thanks in advance for the help.

Rob G
Seattle Area

References

www.se.com

SC3042M200PS - All in one, Homeline, CSED, ringed socket, 200A, surface mount, 30 spaces, 42 circuits, 22kA SCCR, no bypass, solar ready | Schneider Electric USA

Schneider Electric USA. SC3042M200PS - All in one, Homeline, CSED, ringed socket, 200A, surface mount, 30 spaces, 42 circuits, 22kA SCCR, no bypass, solar ready.
www.se.com www.se.com

NM-B panel entry question

So I've come a cross a simple little thing that has me scratching my head. Guy has his house panel in his garage. Since he has installed a surface mounted manual transfer switch ahead of the panel, he decided to install the panel on the surface rather than flush (recessed between the studs)...
forums.mikeholt.com

NEC 312.5(C)

NEC 334.30

rack-a-tiers.com

Wire Waffle - Multiple NM Cable Connector - Rack-A-Tiers Since 1995

Installed in 2.5” panel knockouts to connect up to 16 different cables through a single hole. Cut labor time down by reducing the number of KO’S electricians will have to open. This one-of-a-kind connector will reduce wear and tear on tools, clean up panels, make panel upgrades significantly...
rack-a-tiers.com rack-a-tiers.com
 
IMO using something like the Wire Waffle is the only code compliant way to bring multiple cables through a single KO. If you watch YouTube you'll see thousands of videos where a chase nipple or terminal adapter is used so I'm guessing that in many jurisdictions they have accepted this method although it is specifically prohibited by the NEC.
 
Yeah I've seen a couple around here that were through the back through a big TA.

What do you think the best method to water proof the Wire Waffle would be?

Rob G
- Seattle

Rob G
Seattle
 
As Infinity said, just put a heavy bead of caulking on the back of the panel around the KO's. Not really any different than sealing around a TA.

We also usually put a bead of caulk around both sides and the top of the panel once its mounted.
 
You could also use an enclosure on the inside of the wall along with a nipple to the exterior enclosure, and then secure each cable to the interior enclosure.

Cheers, Wayne
 
  • Like
Reactions: MTW
marmathsen said:
We're working on a DADU where we are wiring everything with NM cable and using an exterior surface mounted meter/main with distribution.
Click to expand...
For this reason along with a list of others I have been asking architects and home designers to design a indoor or covered 110.26 space for a panel, I feel like designing space for electrical and mechanical systems should be taught in architecture school, I have spoken to about a dozen architects about this and they all had no idea . most do it now, so spread the word.
With all the A/GFCI's breaker being out in the elements is not the best for longevity of the sensitive electronics in a AFCI, and the tiny amount of heat the electronics thy put out is attractive to insects like ants.
But sometimes you gotta live outside, we use the Brigeport Mighty Merge 630-NM2
1751985555377.png
 
tortuga said:
For this reason along with a list of others I have been asking architects and home designers to design a indoor or covered 110.26 space for a panel, I feel like designing space for electrical and mechanical systems should be taught in architecture school, I have spoken to about a dozen architects about this and they all had no idea . most do it now, so spread the word.
With all the A/GFCI's breaker being out in the elements is not the best for longevity of the sensitive electronics in a AFCI, and the tiny amount of heat the electronics thy put out is attractive to insects like ants.
But sometimes you gotta live outside, we use the Brigeport Mighty Merge 630-NM2
View attachment 2578614
Click to expand...
I have never seen that connector in person but it would definitely not be my choice for this application. It requires a large hole for few cables. Better off using multiple 1/2 connectors for 2 cables or 3/4-1 " connectors listed for multiple cables.
 
Wouldn't this likely be a violation of 334.10(B)(4)? I am assuming an N3R enclosure, if it was N3 it would be legal.
 
wwhitney said:
You could also use an enclosure on the inside of the wall along with a nipple to the exterior enclosure, and then secure each cable to the interior enclosure.

Cheers, Wayne
Click to expand...
True. This would allow for a single or maybe 2 penetrations which seems easier to seal.

Although this is a small backyard cottage with no great spot for a panel inside which is why we opted for an exterior panelboard. So an enclosure inside kinda defeats the purpose.

Rob G - Seattle

Rob G
Seattle
 
tortuga said:
Brigeport Mighty Merge 630-NM2
Click to expand...

curt swartz said:
I have never seen that connector in person but it would definitely not be my choice for this application.
Click to expand...

I agree with Curt that it doesn't seem like the right application for this connector but good to know it exists. Sometimes your access into an enclosure is limited and a product like this would come in handy.

Rob G
Seattle
 
tortuga said:
For this reason along with a list of others I have been asking architects and home designers to design a indoor or covered 110.26 space for a panel, I feel like designing space for electrical and mechanical systems should be taught in architecture school, I have spoken to about a dozen architects about this and they all had no idea . most do it now, so spread the word.
With all the A/GFCI's breaker being out in the elements is not the best for longevity of the sensitive electronics in a AFCI, and the tiny amount of heat the electronics thy put out is attractive to insects like ants.
Click to expand...
How long have I been saying this? I agree, architects and engineers usually don't consider electrical and mechanical that sometimes require space accommodations and their attention. Receptacles in a 1x furred out concrete wall is one example. They have no knowledge of what's involved or required. Same with locating service panels on the outside of the house. During original design I can't think of any reason not to accommodate it inside except for ignorance.

It's time for the Code to prohibit outside service panels. Then there will be no excuse.

-Hal
 
I don't see an issue coming into the back of the enclosure if it is properly sealed. If this isn't permitted then every AC disconnect, generator inlet, FS box, etc. that I've ever seen with an NM cable connector into the back is a violation.
 
infinity said:
I don't see an issue coming into the back of the enclosure if it is properly sealed. If this isn't permitted then every AC disconnect, generator inlet, FS box, etc. that I've ever seen with an NM cable connector into the back is a violation.
Click to expand...
I actually tell my students they need to use NMB or UF for that run.
 
infinity said:
I don't see an issue coming into the back of the enclosure if it is properly sealed. If this isn't permitted then every AC disconnect, generator inlet, FS box, etc. that I've ever seen with an NM cable connector into the back is a violation.
Click to expand...
But those cases are unavoidable. With a service panel you have a choice.

-Hal
 
You must log in or register to reply here.
Top