I am putting in a RV pad and I need a 30amp electrical service what Gage of wire do I need it will be aprox 200' run maybe a little less
at least 8 ga but 6 would give you the assurance for the distance and voltage drop
30 amp is size 10 awg or american wire gage sizing.
Assuming you are using 240 volts you can run #10 AWG the voltage drop will only be 7.2 volts not enough to be of any worry, The same goes for 120v @ a 7.2 volt loss using # 10 AWG
HVAC Tech.: While 10ga wire would likely handle the load you will be much safer with an 8ga Multi stran, because of the distance involved.
Well I can only comment from the UK regulations. A 30A supply over a 75 metre run would need a large cable as the voltage drop due to the cable resistance would be high, and as you are using 120V you can't afford to loose too many volts through resistance. I would use a 16mm square cable, that has a core (copper) diameter of around 1/4 or just less. I will let you convert that to AWG. I suspect you will also need a Ground Fault Interrupter on the circuit at the origin as it is an installation outside, use the standard 120 volt couplings that you normally use with your RV supply.
