Is my new, 278 ft water well, wired in safely? Electrician ran 100 ft of #6 wire from ( transfer switch out to well house control box ) & then ( 278 ft of 3 wire #12 going down csg to 1 1/2 hp pump ) 378 ft combined wire.
I checked the “Franklin Electric AIM” manual pages ( 14 & 15 ) and the calculations are shown to be acceptable @ .96 maximum allowable voltage drop to meet NEC recommendation of less than 1.0
My issue is that my “Reliance Transfer Switch )has #10 wire running from the 230 volt double pole breaker to the house panel box. So wire starts out at breaker as 4 ft of #10 wire, connected to 100 ft of #6 wire out to well house controll box, then 278 ft of # 12 ( 3 wire ) running down to pump.
The number 10 wire at transfer switch seems too small, but it comes factory wired this way, what do you guys think ?
Best Answer
If the 12AWG submersible pump wire is fine, then the 10AWG in the transfer switch is certainly fine too
A circuit's ampacity is set by the thinnest wire in the circuit. As a result, since we know that there's 12AWG wire in the circuit (going downhole to the pump), the 10AWG wire between the house panel and the transfer switch is fine.