The meter base/disconnect has raised bulges on the back where the mounting bolts go. I simply used four identical galvanized pipe couplings (female thread that doesn't show) and used them as spacers, with long 1/4-20 bolts (could have been 5/16, don't remember) thru the meter base, thru the spacers, thru the metal and thru the 3/4 plywood on the inside. The plywood is rounded on the edges of both sides so it doesn't cut the insulation, and where the edges contact, the insulation is doubled up with insulation repair tape. I used self locking nuts and large fender washers on the inside. The bulges in the back of the meter base were perfect for centering up the "spacers" on the bolt holes, and making them stay there.
The hole in the sheetmetal and the plywood is the exact size of the conduit, and the conduit end fitting on the outside is exactly the same depth as the metal "spacers" so the edge of the conduit end fitting butts against the metal. This hole along with the spacers are sealed with clear RTV.
Most electrical people will screw a couple of pieces of Unistrut horizontal to the ribs of the building and then mount the meter on it, a horrible looking installation, and the Unistrut usually begins to rust after a couple of years.
The panelboard inside does not have a service disconnect or main, as the one outside is acceptable and within easy reach. What I probably should have done would have been to mount the panelboard "upside down" so the main lugs were all on the bottom and it would have eliminated the routing of cables up both sides of the inside of the panelboard, Lots less clutter.
I placard everything so if I drop dead, no one will be left wondering about anything to do with the electrical. At the top of the panel, labeling indicates that there is no service disconnect in the panel and to use the one outside. I took a sharpie and filled in the stamped numbers on the face of the panel (breaker numbers). The A side hot lug is designated as the red side and so identified, this is the first, third, fifth rows of breakers, etc. The right side hot lug is the B side, and is identified with black sharpie, second row, fourth row, sixth row, etc. Every switch and receptacle is identified with what breaker or breakers disconnect it (using a Brother label maker). The receptacles in the roof, for the lighting (a multiwire circuit, double pole breakers and switches and split receptacles) have large red letter A next to the top plug and large black letter B next to the lower plug, so you can stand on the floor and see what side the light is plugged into. The unused side is covered with a push in receptacle cap, one of those "child proof" covers, keeps the dirt daubers out of the ground pin holes.
In the pic above the lower third of the inside of the panel door is the labeling for the breakers, by number, voltage, and description of what is on the circuit. I allowed space to add labels later, as I started adding breakers at the bottom and working up, except for the surge protectors on the top left and the 60 amp subfeed breaker below it.
The mess of receptacles below the panel was all I had in the building for some time. A 50 amp 240V three prong receptacle for my welder, a 30 amp 240V receptacle for a portable air compressor I had (and anything else that needs it), a 20 amp receptacle in case I encountered a 20 amp plug on a cord of a mig welder, etc (very unusual) and a box with two 120V receptacles on two breakers.
I removed the switch box arrangement and installed something different.
Charles
