What wire should you use for 240V?

Answer 1

This question raises many others. Are you wiring in an office, a barn, or a house? Is the application to wire a pool pump, sump pump, an air conditioner, an oven, a heater, or what? Where is the appliance located? Is it new or existing? Is it installed and grounded? How far is the application from the main electric panel? Is the wiring to run outdoors or will it be exposed to moisture, extreme temperatures? Will it be run inside a wall or left exposed? What is the amperage rating of the appliance or machinery or heating device? Will this line be dedicated to one appliance or machine? Have you identified the breakers to be used? If so what is the amperage rating? Is the circuit protected? Is your electric supply single phase two wire, three wire, or 3-phase current? In what U.S. State is the intended application? I am sorry. Your question cannot be answered. You see, the fact is if you did not know enough about electrical matters to realize that the question lacked vital detail you should not be doing your own wiring and should hire an electrician for this job. It is too dangerous to do it yourself. This doesn't mean you cannot learn. If you are very interested in obtaining more knowledge you might start with one of the more elementary but thorough paperback books: Wiring Simplified by H.P. Richter if still available. It was published by Park Publishing, Inc., 1999 Shepard Road, St. Paul, MN 55116. Good luck!