3 awg vs 6 wag length 100 feet and over

[RAM1950]

I'm expecting delivery of my preowned P85 in 2 weeks. Should I spend the extra$ and upgrade my home charger wiring to 3awg from 6awg. The length of wire required will be near or slightly over 100 ft. I will charging at 40 amps Nema 14-50 connector.

 

[kennybobby]

Not if the 6awg is copper wire, but if aluminum then yes. At 40A with copper you only drop 3 volts for that run, with 3awg copper you drop 1.5 volts.

 

[RAM1950]

Did you mean at 40A with aluminum you drop 3 volts?

 

[kennybobby]

No with aluminum it would drop 6 volts, but 40A is right at the limit for 6 AWG aluminum, 3 wires in a cable, UF TW wire, etc. FlasherZ is the expert on NEC, i'm just doing voltage drop calculations...

 

[RAM1950]

Thanks for your guidance

 

[Khatsalano]

My dog likes 6 wag.

 

[Cottonwood]

My dog likes 6 wag.

And in my engineering world a WAG is a Wild A** Guess...