Welders, 10-ton ac units

[Military Electrician]

Hey y'all,

Very inexperienced here, and strugglin'. I need to hook up a welder and a 10-ton ac unit. I have tried to get my head around the nec with regards to these calculations, but...

We are gonna just take the nameplate data and wire these things accordingly, but just for my own info what should I consider with all of this 115%, and 300%, locked rotor, etc?

Any help will be greatly appreciated. We have very limited resources here and my main focus is safety. There is no Authority Having Jurisdiction here. Just the soldiers and taliban.

 

[beanland]

Check the Nameplates, if any

Check the Nameplates, if any

Starting place is to check the nameplates on the welder and A/C unit. They will give FLA (full load amps) or MCA (minimum circuit amps) or MCP (maximum circuit protection.) If you have FLA and it is a single device, use 125% for the MCA. Put in wire for the MCA. The wire size tables in the National Electric Code assume 30C ambient. If it is 45C, you will need wire with 50% more NEC ampacity just to keep the wire from overheating. Use the 75C wire rating table because the limit is based on the connections on either end.

Size the fuses or circuit breaker per the MCA. If the nameplate MCA is 30A, you will need 45A-rated wire and a 30A-40A breaker.

Hope it helps.