Hi,
I want to run 220 volt, 50 amp cable to a workshop that is about 150 feet away from the house. Can you tell me what cable to use, and anything to look out for?

Thanks
tabriz

 

Just wanted to add the electricity will be for a welder and plasma cutter.

tabriz

 

Are your plans to run it underground, direct bury or in conduit, or overhead?

 

We're planning on underground.

 

Do you already have or plan to have 120v at the work shop? If so you will need to install a subpanel and abandon the 120v. Code generally does not permit more then one circuit.

 

Yes, we already have 120 there. So what do we do cable wise?

 

How big is your main panel? What other loads do you have in the shop? Model number and specs for the welder. The pros will be able to better help you with those answers.

 

#8 Should suffice THHN in conduit

 

Post deleted.

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You would need to set a subpanel to power the shed. Only one circuit is allowed code-wise to feed your outbuilding.

This might mean increasing the size of the feeder to the shed.

 

Number 8 would not be adequate. The feeder cable needs to be sized for a subpanel that can power everything. Also since it is more then 100 feet you may need to increase by one at least. Without knowing all loads we can't really say. You might get buy with a 70a breaker at the main panel and #4 copper or #3 aluminum if just lights and welder. Lights might dim when welder is used. There would be no spare power for say a compressor while using the welder.

 

Thanks, everyone. I'm going to get my husband in on this conversation since he will be doing the work and knows electricity (and I don't!).

 

Put your waders on and stay in the water. You'll learn a lot.

 

the cheapest/most effective way to do this would be to run aluminum feeders, as you would a house. #2 aluminum with nolox is good for 100 amp subpanel. This is what I do for any garage that wants more then a simple 110v circuit to run a sander or sawzall.

Aluminum, you can only use for feeders. So you would have to feed a sub panel, Which is your smartest bet anyway. You can get both 110v and 220v. Plus you can have several circuits. For general receptacles, welders, a big honkin air compressor, a lift.

What you need to do is dig a 18" trench, run 2 inch conduit, and pull number 2 aluminum triplex. Also take into consideration if your ever going to want cable tv, alarm or telephone in this building. This would be the time to bury a 1" seperate plastic conduit right along side the 2 inch. Its cheap, and you can leave it there until your ready to pull low voltage though it. The low voltage and line voltage have to be in seperate conduits.

All this is assuming you have a 200amp main panel. If you only have 100amp, I would recommend a 60 amp subpanel and just dealing with the lights that will be dimming.

 

Strider.,

If the OP is on 2005 or later NEC code cycle there are few issue it will affect the conductor rating the #2(35mm²) AL SER conductors they are only good for 90 amp even you run the THWN Alum verison sometime we called XLP { this item is restricted to outdoor only } that still on 90 amp max due the tempture rating on the conductor.

I know you will say something about this but if you have NEC codebook you will see why they derated this conductor / cable assambly as feeder circuit that you have to follow 60°C rating even thru the conductors are good for 90°C rating but if you run THHN/THWN copper conductors then you can get by with 75°C rating

The other thing If I did not catch what location where the OP is from some states you required to bury the conduit or cable at least 24 inch deep { I know in State of Wisconsin do require cable to be at least 24 inch but in rigid conduit ( both plastic and steel verison ) you can get by with 18 inches but for myself just stick with 24 inches and it will have no issue with it.

Also I wrote underline the triplex is no longer allowed with new subpanel feeds you will need 4 conductor type which it will have two active{ live } conductors and netrual and ground conductor.

The min size with 4- #2AWG conductors is 1.5 inches { really some case you can sqeak by with 1.25 inch conduit but not worth it espcally if you have more than two 90° ells there }

Merci,Marc