30A Generator 'Input' Plug: Surface vs Flush Mount On Stone Wall?

[pgtr]

In construction phase of new house and garage...

I am pre-wiring a 30A input plug on the side of the garage. This will be wired to the sub-panel inside the garage where there will be an inter-lock switch. I'll then be able to wheel a portable generator out the driveway, around the corner and plug it into the input plug if needed during an extended power outage. (then I can manually select just a few pre-identified circuits at the sub-panel to power up, staying within the capacity of the portable generator.

I picked up a Reliance PB30 input plug receptacle. It is designed to be a surface mount.

QUESTION: Is flush mounting in stone siding reasonable? Or bad idea? They are starting on the stone siding and the stone masons can set it in the stone. If so they would have to leave a 3/4" or so gap above the plug so I can lift the cover off. I'd probably have it stand proud of the stone by about 1-inch. (not perfectly flush but close)

Or leave a simple 'hole' in the stone siding and let the wire come thru (stub a piece of gray conduit there) and surface mount directly to the stone. This would give me lots of stone to drill into for a secure surface mount.

Or I can put a single gang box (or 2 gang) and push a little extra wire inside if I need to pull some excess out and mount the PB30 box on top of the gang box. One problem here is that the PB30 mounting holes don't line up well w/ the gang box - maybe drill my own holes and screw directly into stone and cover the gang box w/ surface mount PB30...? (I could also rotate the gang box 90* horizontal and give me more space above below for mounting PB30 into stone and still cover up gang box on sides...)

Appreciate your input on options for mounting a Reliance PB30 on/in stone exterior siding - thanks

 

[larry4406]

I would be inclined to surface mount it.

Also there are other styles which there is a nice hooded in use cover to protect the junction from rain while plugged in.

Have your mason embed a portion of a solid CMU trimmed to match the size of your inlet box so you have a nice flat spot to mount.

 

[MongoTA]

I like larry's recomendation.

If you want to flush mount it, I'd also consider mounting a piece of 2x4 or 2x6 the appropriate size, screwed into the wall sheathing at the proper location. Maybe run the 2x6 through the table saw to cut it in two, then screw the two pieces to the sheathing with a slight gap between them. Wrap the of wood with a couple wrappings of foam sill seal. The gap between the two pieces and the sill seal will give you wiggle room to remove the pieces later on.

If you want to surface mount, run a piece of PVC pipe through the wall. Use the PVC as a sleeve to run your conduit through when you mount the surface-mounted box.

They can then stone right around the chunk of wood or the PVC.

Slight tangent...I have na APC panel for my generator, the APC Universal Transfer Switch 10-Circuit – Bypass switch – AC 120/240 V. Love the thing. You can wire quite a few circuits in, it's programmable so you enter your circuit priority for load shedding, etc. It load sheds as needed, as you have programmed it. The 240v circuit runs my well pump, the way I wired it up the well pump is the only 240v in my house that can be powered by the my generator, a Honda eu6500. But pretty much every other 120v circuit in my house can be powered; kitchen bathrooms, bedrooms, offices, home theater, etc. Pretty nifty. I've had it for over a dozen years with no issues. Longest outage we've had was 8 days in the summer and 5 days in the winter. APC was ~$400 when I bought it way back when. Good for when I'm not home and my wife is here alone. She turns the key to start the generator and the transfer panel takes care of the load management.

 

[dcg9381]

Mounting to stone *****. I'm with Larry. There are good materials like PVC that won't need any exterior maintenance. In a pinch, I've used wood, coating it in 2 coats of epoxy and then paint. Definitely do the PVC conduit in advance.

 

[dave*99]

I used a different raintight inlet. The PB30 is outdoor rated, but I prefer the connector orientation in this unit:

https://www.amazon.com/dp/B009TNTXDO/?tag=atomicindus08-20

 

[CJ7VFR]

I would be inclined to surface mount it.

Also there are other styles which there is a nice hooded in use cover to protect the junction from rain while plugged in.

There are also power inlet boxes with the inlet on the bottom of the box to hook the generator cable to. I have one of these for my portable generator hook up to my house. Because the inlet is on the bottom, it retains its in use ability without having to have any other type of cover on the box. Here is a few shots of mine. Jim

 

[Noltz]

I've got one like CJ7VFR, surface mounted bottom-in. These are better because the cable isn't stressed when plugged in and rain/snow doesn't accumulate. Door is spring loaded. These would have to be surface mounted though because the door would hit the stone. If your mason has a suitable color flat stone that would allow well-sealed surface mounting I'd go with this. Find a discrete corner for this utility.

If I can make one suggestion; When you wire it use 8 gauge individual conductors, not NM. I used 8-3 NM-b thinking I could bump to 50A inlet if I ended up with a bigger generator. Turns out romex is only rated to 45A. Now I have a 12k generator and I can't use it all. 30 is great, but 50A would let me comfortably run my central AC.

 

[AP514]

+1 on the botton outlet like CJ7VFR posted....

 

[mike93lx]

I've got one like CJ7VFR, surface mounted bottom-in. These are better because the cable isn't stressed when plugged in and rain/snow doesn't accumulate. Door is spring loaded. These would have to be surface mounted though because the door would hit the stone. If your mason has a suitable color flat stone that would allow well-sealed surface mounting I'd go with this. Find a discrete corner for this utility.

If I can make one suggestion; When you wire it use 8 gauge individual conductors, not NM. I used 8-3 NM-b thinking I could bump to 50A inlet if I ended up with a bigger generator. Turns out romex is only rated to 45A. Now I have a 12k generator and I can't use it all. 30 is great, but 50A would let me comfortably run my central AC.

8/3 NM-b is only 40a rated, but if it was rated for 45a, a 50a breaker would be allowed since 45's don't exist. Editing based on @sparky 1971 's correction below

6/3 would work for 50a

 

[sparky 1971]

8/3 NM-b is only 40a rated, but if it was rated for 45a, a 50a breaker would be allowed since 45's don't exist.

6/3 would work for 50a

Yes they do. Just not carried in the box stores. About the only time they will get used is for motors or air conditioners, but they do exist along with 25's and 35's.

 

[mike93lx]

Yes they do. Just not carried in the box stores. About the only time they will get used is for motors or air conditioners, but they do exist along with 25's and 35's.

"Mr I use 100's on #2".... Shhhh, if we deny their existence we can upsize

 

[sparky 1971]

"Mr I use 100's on #2".... Shhhh, if we deny their existence we can upsize

A 90 didn't exist in my inventory. So I upsized. Besides, it was my own place. It's not like I paid someone to do an install that wasn't up to code.

 

[mike93lx]

A 90 didn't exist in my inventory. So I upsized. Besides, it was my own place. It's not like I paid someone to do an install that wasn't up to code.

I know, I'm busting balls

 

[justsam]

Here is my surface mount on exterior wall. Manual transfer is inside load center. Since I installed it, I have not needed to use it! Generator is Honda 7000 with remote capabilities, and running on non-ethanol fuel.

 

[mike93lx]

Here is my surface mount on exterior wall. Manual transfer is inside load center. Since I installed it, I have not needed to use it! Generator is Honda 7000 with remote capabilities, and running on non-ethanol fuel.

That's the best generator to have...one you never need.

Not many people do a 50a plug

 

[CJ7VFR]

Here is my surface mount on exterior wall. Manual transfer is inside load center. Since I installed it, I have not needed to use it!.....

This seems to, luckily, always be the case! Which is a good thing!

Jim