My new shop is finally under construction , and the electrician should be showing up in about a week to start the wiring. I have a question on the wiring and circuit breaker size for 3 HP motors.
I will have individual 220V circuits for all of the heavier machines (air compressor, dust collector, lathe, tablesaw, bandsaw and planer). Each of these will be 3 HP motors.
None of the wiring runs will exceed 50 feet from the 200 amp sub-panel.
The best information I can find says I should size the circuit based on a 3 HP motor drawing 17 amps, and sizing the circuit for 125% of the load. That would mean each of these circuits should be sized for 21.2 amps. This means a 30 amp circuit and 10 gauge wiring.
Does that sound right? My gut feeling is a 20 amp circuit with 12 gauge wire would be ok. Are there any of the above machines that should definitely be on a 30 amp circuit?
Thanks, Mike