THWN. Underground conduit is a wet location, you need wet-rated conductors. Most THHN is also marked THWN however.
NO AFCI's in the workshop please. ****ed things trip all the time in my house when I plug in small motors.
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NO AFCI's in the workshop please. ****ed things trip all the time in my house when I plug in small motors.
Pulling thick wire through conduit with ELs is much HARDER than you think. Don't assume you can pull later without digging up. Better to spend the extra up front and just get the larger wire.
60 amp will probably be gracious plenty for a one-man shop. However, the primary advantage to going to a higher capacity box is getting more slots for more circuits. But the cost of the bigger box itself isn't much more. So go for the biggest box you can afford. It's the breakers that add up. If you run a table saw, DC, lights, AC and a radio all at once, you're not going to even come close to 60 amps and that would be your worst case scenario.
But given the small size of your shop, you're not likely to have a whole bunch of tools, lights and other things that run at one time. Nor will you have lots of room for lots of different circuits. So I stand by my original statement: 60 amps is plenty for your shop.
You're probably not going to have enough bare walls to lean a lot of plywood against the wall so I wouldn't worry about that either.
Put lights on separate circuits.
Always make sure there is a DC outlet on a separate circuit from your table saw and other tools. The only two big power drains that will run at the same time are as other tools are either a compressor or dust collector. Make sure at least those two are also on a separate circuit.
Allow a circuit for HVAC. Window units work well for a small shop and in this part of the country can make summers much more bearable.
If you run larger gauge wire to switches and receptacles, make sure you buy switches and receptacles that will handle the larger wire. Some don't come with the ability to fit the larger wire in the quick-connect holes.
Running 10 gauge wire to your 220V circuits makes some sense. Otherwise, I would not run oversized wire. Copper wire is pretty expensive right now and the benefit is marginal. Current wire size requirements already has a built in margin for error. The only exception might be on circuits where you might reasonably expect to upgrade it later. Keep in mind that going from a 110V to a 220V tool will probably NOT increase the amperage requirements. If anything, they will decrease. Even if you triple the horsepower, the amperage will not be triple due to the second leg being out of phase. (sorry for the technical stuff but it is true). So if you currently have a contractor's table saw, you won't need to run new wire to upgrade a 20 amp 110V circuit to switch to a cabinet saw. You'll just need to replace the breaker and the receptacle.
Make sure you have a few empty slots in your panel box when you're done. In order to upgrade a circuit from 110 to 220, you'll need to replace the single pole breaker with a double pole - hence the extra space.
I envy you. This is the part of building a shop that's the most fun IMHO.
60 amp will probably be gracious plenty for a one-man shop. However, the primary advantage to going to a higher capacity box is getting more slots for more circuits. But the cost of the bigger box itself isn't much more. So go for the biggest box you can afford. It's the breakers that add up. If you run a table saw, DC, lights, AC and a radio all at once, you're not going to even come close to 60 amps and that would be your worst case scenario.
But given the small size of your shop, you're not likely to have a whole bunch of tools, lights and other things that run at one time. Nor will you have lots of room for lots of different circuits. So I stand by my original statement: 60 amps is plenty for your shop.
You're probably not going to have enough bare walls to lean a lot of plywood against the wall so I wouldn't worry about that either.
Put lights on separate circuits.
Always make sure there is a DC outlet on a separate circuit from your table saw and other tools. The only two big power drains that will run at the same time are as other tools are either a compressor or dust collector. Make sure at least those two are also on a separate circuit.
Allow a circuit for HVAC. Window units work well for a small shop and in this part of the country can make summers much more bearable.
If you run larger gauge wire to switches and receptacles, make sure you buy switches and receptacles that will handle the larger wire. Some don't come with the ability to fit the larger wire in the quick-connect holes.
Running 10 gauge wire to your 220V circuits makes some sense. Otherwise, I would not run oversized wire. Copper wire is pretty expensive right now and the benefit is marginal. Current wire size requirements already has a built in margin for error. The only exception might be on circuits where you might reasonably expect to upgrade it later. Keep in mind that going from a 110V to a 220V tool will probably NOT increase the amperage requirements. If anything, they will decrease. Even if you triple the horsepower, the amperage will not be triple due to the second leg being out of phase. (sorry for the technical stuff but it is true). So if you currently have a contractor's table saw, you won't need to run new wire to upgrade a 20 amp 110V circuit to switch to a cabinet saw. You'll just need to replace the breaker and the receptacle.
Make sure you have a few empty slots in your panel box when you're done. In order to upgrade a circuit from 110 to 220, you'll need to replace the single pole breaker with a double pole - hence the extra space.
I envy you. This is the part of building a shop that's the most fun IMHO.
Seems like there is tons of advice on how to size the run to your workshop. So I will pile on 
. When I did my garage the economics decided for me. Running main line was ~45-50 feet and if memory serves it cost half as much to run 90A in aluminum then it would have cost to run 55A in copper (and I couldn't find a 55a breaker ).
I know someone will chime in with the relative merits of copper over aluminum and I won't debate them. But the other large run to my main circuit breaker that feeds the whole house (except for the HVAC) was already aluminum. And if I am not mistaken the buried cable that brings 200a service into my house is alu as well.
Good luck and keep us posted!
Salem
. When I did my garage the economics decided for me. Running main line was ~45-50 feet and if memory serves it cost half as much to run 90A in aluminum then it would have cost to run 55A in copper (and I couldn't find a 55a breaker ).I know someone will chime in with the relative merits of copper over aluminum and I won't debate them. But the other large run to my main circuit breaker that feeds the whole house (except for the HVAC) was already aluminum. And if I am not mistaken the buried cable that brings 200a service into my house is alu as well.
Good luck and keep us posted!
Salem
In my new shop I used 100 AMP aluminum feeder wire from my house box to the 100 AMP service box in the shop. I have a 90' run. The aluminum wire is roughly 1/2 the cost of copper. I also installed 2 earth ground rods thanks to a advise of a good friend. :wsmile:
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