What size EMT, & PVC would be used if you were going to run on 30 amp 220 volt circuit. the run would be 10/2 romex pushed through this. I have been told that it requires 3/4" but every thing i have ever been tought tells me 1/2 would be fine. It is 2 conductors and a ground all solid 10awg copper. These hit a weather proof box befor going to pipe, it it required to strip down the romex from its outer jacket pprior to being fished.
