Wire for 50A 220V Service - 110' run

BurbMan wrote:
60 Amp is too big for the #8 wire you have running to the barn. That should be a 40a double-pole breaker at the source. I believe that NEC requires a disconnect for all sub-panels so you should have a 40A double pole as the "main" in the barn, then a 30A double pole for the RV plug and a 15A single pole for the light circuit.

Somebody please chime in if this is not correct.

When I wired my shop 10 years ago a main wasn't need in the subpanel so long as there were at most 3 subcircuits and they were labled "main". That may have changed by now and a main sure doesn't hurt anything.

The key thing was what I posted a few posts above: The 2 hots must be on opposite legs of 240V which means they need to be on one breaker. That breaker must be sized to the wire's capacity which is certainly not 60A. Never use 2 hots on the same breaker terminal and never connect them to the same leg with only one neutral.

60 Amp is too big for the #8 wire you have running to the barn. That should be a 40a double-pole breaker at the source. I believe that NEC requires a disconnect for all sub-panels so you should have a 40A double pole as the "main" in the barn, then a 30A double pole for the RV plug and a 15A single pole for the light circuit.

Somebody please chime in if this is not correct.

OK, here's what I did:
Enclosed the exposed cable in conduit. Using a 60amp breaker off the pole, used all four wires in the cable (previously, one wire was not used). Installed another breaker box in the barn, two hots, one neutral and one ground. Using two 30amp breakers to feed the 4-pin RV outlet. Separate 10amp circuit for the lights in the barn.
I'll have my son-in-law check everything to make sure I don't curl my hair.

GM

Thanks, Dick. You get a free pass on raids for another year.
My son-in-law is an electrical engineer. He helped me re-wire my house recently, all the way from the pole to the 200amp breaker box inside. I've asked him about his before and his recommendation was quite similar to yours. I"ll have him take another look at the existing wiring, discuss the various options recommended here and then probably ignore him again. ;-) Actually, I rely on him heavily when it comes this type of job.

Incidentally, I will be in NE Washington in June, planning on spending the night of June 11th at the military Fam Camp just off the Interstate. Maybe we can get together and invent some lies.

Lonnie

Lonnie,

If you really want to do the job right purchase enough 1-1/4" PVC conduit and Thhn stranded wire at a local electrical distributor. You should purchase the correct lengths of #6 wire in white (neutral), black (L1), red (L2) and green. The green conductor is a protective ground and I think code still permits #8 for this conductor.

The THHN wire will cost about $.55/ft (Currently $.54/ft at Platt Electric - platt.comm. I recently purchased three 500' rolls for use in wiring my new shop building and I think the cost was about $750.

PM me if you want additional information.

Grey Mountain wrote:
The wire currently in use is old - it was there when we bought his place 27 years ago. At the time, it did not extend into the barn. There was no electricity at in the barn since its primary purpose was for hay storage. The wiring exits the pump house and is exposed to sunlight for about two feet. The rest of the cable is buried and surfaces inside the barn where I have the breaker box. Although I've had no problem, I was a bit afraid that the unprotected cable may have deteriorated due to exposure to sun and the elements. And since I had the other wire on hand, it looked like a possible fix. Having read all the replies, it seems logical to install two 30amp circuits using the existing four wires. At present, one of those four is not connected to anything.

Many thanks to those who know a lot more about sparks than I. Also many thanks to those who know even less than I about sparks, but were willing to give it a shot... :-)

GM

I hope you mean install one 240V/30A circuit. Since those circuits will share a neutral, they should be on a 240V common trip breaker. After that they can be considered seperate 120V/30A circuits but using the proper breaker is key.

Connecting a 50A 4-pin RV outlet to that breaker would allow you to plug directly in.

Consider some conduit to protect the existing cable as it emerges from the pumphouse and enters the ground.

(Grey Mountain)

Now THERE goes a gentleman...

The wire currently in use is old - it was there when we bought his place 27 years ago. At the time, it did not extend into the barn. There was no electricity at in the barn since its primary purpose was for hay storage. The wiring exits the pump house and is exposed to sunlight for about two feet. The rest of the cable is buried and surfaces inside the barn where I have the breaker box. Although I've had no problem, I was a bit afraid that the unprotected cable may have deteriorated due to exposure to sun and the elements. And since I had the other wire on hand, it looked like a possible fix. Having read all the replies, it seems logical to install two 30amp circuits using the existing four wires. At present, one of those four is not connected to anything.

Many thanks to those who know a lot more about sparks than I. Also many thanks to those who know even less than I about sparks, but were willing to give it a shot... :-)

GM

smkettner wrote:
It is a solution looking for a problem.

Somebody finally caught on. ;-)


GM