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Mike G.
Mike G., Master Electrician
Category: Electrical
Satisfied Customers: 7590
Experience:  Proven Professional 48 years Experience
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Okay. I am trying to determine if I need 4 AWG or 3 AWG to

Customer Question

Okay. I am trying to determine if I need 4 AWG or 3 AWG to wire the service lines from a 18kw standby generator with a 40' run. My issue in reading the ampcity charts is understanding the 60c vs. 75c vs. 90c temp columns using THHN wire.
JA: I'll do all I can to help. How long have you been dealing with this?
Customer: researching getting ready to start the work.
JA: Do you plan on doing the work yourself?
Customer: yes
JA: Anything else we should know to help you best?
Customer: Will be run in conduit (PVC interior and flex outside to the generator. Will also be running 14awg 600v THHN control wires.
Submitted: 11 months ago.
Category: Electrical
Expert:  Mike G. replied 11 months ago.

Hi, I'm Mike and I'll be assisting you. Please stand by while I review your question.

Expert:  Mike G. replied 11 months ago.

The #4 copper will be acceptable for the installation.