Grouping of disconnects for feeders to separate buildings

[LarryFine]

If you can, have the customer dig a trench across the building for some additional PVC.

Wish I could, but the floor has already been poured. I did request they form a 6"x6" recess in the floor under the wall at the proposed panel location for the feeder.

 

[MTW]

It can be difficult to get forewarned in time. Build first, electrify later. It's nice when you have good customers that call before they start.

Up over and down, would likely be easier than short radius elbows, behind columns.

MTW

 

[LarryFine]

The ceiling is quite high, around 20', and he wants receptacles on three walls, and future expansion capability, which is why I'm proposing 3/4" EMT around the walls; no ladder needed later, just extend from the receptacle boxes (2 per wall).

I also have the option of running NM instead of 1/2" EMT above 10' for the interior (4 lights) and exterior (3 lights) lighting, which also makes it less convenient to take the ceiling route for the other walls. The garage is 26' x 30' by the way.

I also want to use a "real" 100 amp main-breaker panel instead of a back-fed plug-on 100 amp main breaker for reliability, and greater wiring space within. They're barely more expensive anyway. Anyone think a 20-space panel is overkill?

 

[LarryFine]

One last question re Table 300.5: How do we determine whether we need 18" or 24" burial depth? What defines "dwelling-related purposes"?

This is the customer's home, but he will drive a commercial vehicle around the outside of the garage building once or twice a week for parking.

 

[MTW]

Dwelling related to me means no commercial or truck traffic. Driving a commercial truck around the building twice a week, To me would qualify for the 24" depth. He's doing the digging, right?

Here in Michigan, I'd be putting it in below the frost line, 42" so I never had to touch it again. Most new lot lighting runs here, fail within a few years when installed at code depths.

For your 3 walls, the up over and down, with EMT and no overhead pull points also means no ladder required in the future. I'm a pipe guy, it seems less work to me than all those cables, staples, boxes and splices on the ladder.

MTW

 

[kwired]

So, does this qualify, and I will be using PVC.

https://www.homedepot.com/p/Southwire-By-the-Foot-1-Black-Stranded-AL-USE-2-Cable-27283190/205001910

Nothing in the page linked to mentions any rating other then USE-2. But that don't necessarily mean the conductor itself won't have other ratings marked on it.

If it is only marked USE-2 an inspector would be correct to reject it if it enters a building.

 

[kwired]

Dwelling related to me means no commercial or truck traffic. Driving a commercial truck around the building twice a week, To me would qualify for the 24" depth. He's doing the digging, right?

Here in Michigan, I'd be putting it in below the frost line, 42" so I never had to touch it again. Most new lot lighting runs here, fail within a few years when installed at code depths.

For your 3 walls, the up over and down, with EMT and no overhead pull points also means no ladder required in the future. I'm a pipe guy, it seems less work to me than all those cables, staples, boxes and splices on the ladder.

MTW

If at a residential only zoned property - it is not commercial regardless of what may drive over it on occasion.

 

[electrofelon]

I also want to use a "real" 100 amp main-breaker panel instead of a back-fed plug-on 100 amp main breaker for reliability, and greater wiring space within. They're barely more expensive anyway. Anyone think a 20-space panel is overkill?

I would probably use one of the homeline 100A main breaker 20 spacers. They're like 55-60 bucks. About the only thing cheaper would be one of the small 6 space homeline horizontal guys,but I dont really like those and they are only like $15 cheaper.