Code check for MWBC to shed
I have some questions about a wiring project I want to make sure is code-proper. As background for me, I work with and design electrical for industrial equipment. So ampacity, signals, complex wiring, 3-phase, it's all cake for me. But we all know a little knowledge is a dangerous thing, and that proper for light manufacturing is not proper for residential. So bear with me please. I have personal and fire safety covered, but it basically ends there. Thank you!
My shed is a simple affair, with normal stud construction but sits on concrete plugs. It is not a permanent structure. Inside this shed I will locate a small compressor (30 gallon) and a dust collector (1.5 HP) and nothing else. It's dedicated for these appliances. I figure roughly 12 amps draw for each device, peak. Maybe less than 10 for the compressor.
What I want to do is run some 12-3 from a 20A 2-pole normal breaker in the main panel to the shed to power two 20A GFCI outlets in a 2-gang box inside the shed. Plug one appliance into each line. Maybe plug an incandescent bulb fixture to the compressor side too.
I know there are normally no issues if I were putting in a light and a dorm fridge, but given this is two pieces of heavier machinery than a 60 watt bulb I thought I'd run it by the experts.
I should be conceptually set via code, yes? Or am I?
Could I also do something crazy like run the 12-3 from the main to a J-box through two 20A light switches THEN to the shed, so I could (theoretically) turn on the compressor or DC independently from inside the house?