Adding additional electrical circuits

[Christopher S.]

Good morning gentlemen, we would like to add (2) additional circuits in the pole building where we store mine and my dads rvs. The main work garage has a 200 amp entrance that feeds a 100 amp sub panel where the rvs are located. From the 100 amp sub panel we would like to add a 50amp circuit for dad and a 30 amp circuit for myself. The 50 amp receptacle would be located about 150 feet from the sub panel. The 30 amp receptacle would be located about 65 feet from the sub panel. What gauge wire would I need to use for each application? Thanks

 

[Steve@Advance]

The 50 amp needs #6 copper or #4 aluminum.

The 30 amp needs #10 copper or #8 aluminum.

 

[John T]

Good morning Christopher, FWIW I agree with Steves answer...Ive owned RV's over 50 years and added many receptacles for plugging them in when stored. I will take a couple educated guesses based on your stating you need 30 Amp and 50 Amp circuits and they are to be used for RV's.......

A typical so called 50 Amp RV uses a NEMA 14-50R 50 Amp Receptacle. For those you need to run FOUR CONDUCTORS (Two Hots L1 & L2, One Neutral, One Equipment Grounding Conductor) MINIMUM 6 GAUGE COPPER CONDUCTORS, protected by a TWO Pole 50 Amp Circuit Breaker. In the event (not all that likely) Line Voltage Drop (based on wire size, current and distance) was excessive you would increase the wire size to 4 Gauge

A typical so called 30 Amp RV uses a NEMA TT-30R 120 Volt 30 Amp Receptacle. That requires a minimum of THREE 10 GAUGE COPPER CONDUCTORS protected by a 30 Amp SINGLE Pole Circuit Breaker.

Do NOT take my word for it (Im long retired n rusty on the latest NEC) consult trained professional electricians and power engineers and/or any applicable local governing authority and when in doubt where fire and life safety are concerned BE SURE ITS DONE PROPERLY

I would NOT use aluminum for this application, again 6 Gauge Copper minimum for the 50 Amp and 10 Gauge Copper minimum for the 30 Amp, my preference would be to run the wires in conduit using THHN conductors. Consider what any professional electricians have to say also.......... I have NO IDEA what breakers may or may not be available for use in your panel so am purposely NOT speaking to that...


Best wishes take care be safe

John T

 

[MarkB_MI]

Are you sure you won't be replacing your RV in the future? You might want to consider skipping the 30 amp outlet and go with two 50 amp boxes. If you upgrade to an RV with 50 amp service, you're already set.