We're building alot of small computer server rooms in all fo the schools in our district.
Each of these is nearly identical and needs a specific number of 120 and 208V recepticles. We've only done a couple so far and pulled each circuit from nearby panels but some weren't all that nearby.
With more than a dozen to go, I got the brilliant idea of installing a small subpanel in each server room. this means pulling less wire and gives easy room to expand in the future.
I need a small three phase electrical panel. The ideal panel would be 60A with 6 breaker positions but something a little larger would work. I'm not so concerned about size (although in some of these closets it is a problem). I'm mostly concerned with capacity. I don't have an available 200A near some of these locations.
The smallest panel I've seen is a 100A 24 position - Much more than I need.
Why does he need a main. Use the 100 main lug panel and supply it with whatever size overcurrent device ahead of it, as long as the device is not more than 100 amps.