220 circuits

[DpSyChO]

In the process of wiring up 220 circuits in shop over the holiday weekend and wanted to double check that I am looking at NEC table correct. I spoke with local building inspector a couple weeks ago about other things, we briefly veered the conversation to wiring and do remember him saying to use the the 75* column. I didnt have a chance to call back before they closed for the holiday.

Plasma circuit on 50a breaker will use 8ga copper

Welder circuit on 30a breaker will use 10ga copper

Vertical bandsaw, horizontal bandsaw, and mill circuits ( all three are 3ph rated at 2hp), each will be powered by individual frequency drives I already have that specs 16a input and each one will be on their own 20a breaker circuit, each circuit will use 12ga copper

Am I on the right track?
Mike

 

[Speedy Petey]

The temp rating column has nothing to do with the load. It has to do with the type of wire.

NM cable NEVER uses anything but the 60 deg C column when figuring ampacity. Yet it uses the 90 deg C column when figuring in derating.

AC/MC cable can typically use the 75 deg C column. As can pipe and wire installations.

The only thing questionable in your setup is the plasma. With MC/AC/pipe you are fine with #8. With NM you'd need #6.

What type of wire are you using?

 

[DpSyChO]

Sorry, left that out.
THHN wire in conduit.

 

[sberry]

The only thing questionable in your setup is the plasma. With MC/AC/pipe you are fine with #8. With NM you'd need #6.

It may depend on the connected machine. I believe a 10 romex connected to a 50 is legal for a buzzer, its legal with 12 in pipe. Welder extension cords come with 8 and 50 ends.

The only thing questionable in your setup is the plasma. With MC/AC/pipe you are fine with #8. With NM you'd need #6.

My plasma is 10 and 50 in pipe.

 

[DpSyChO]

Plasma = Powermax 45
Welder = Millermatic 175