I have an 8 Kilowatt 110V DC motor which will be started on load. What size of wire and Overload should I use?

Question

This will be service wiring or air wiring and is in a building and the maximum expected ambient temperature is 35 degrees celcius. This motor will be running a high pressure pump.

Answer 1

Get a qualified electrician to do this for you, and in all cases, follow the code.

I find it odd that you'd have 8kW at 110V... the amps are VERY high on this.  You should be running 480V 3 phase for this size of motor... 240V 3 phase would also work if that's what you've got.... but not 110V.  Seriously, get an electrician and/or an electrical engineer.  s******g this up could kill somebody (including you), or cause some very expensive damage.