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jhesse
Apr 6, 2009, 11:24 AM
I have 200 amp service coming into my home. I want to wire my shop which is 130 ft from my panel box. Going to have about 20 120volt outlets, 20 lights. Also will have air compressor, and maybe a welder, so I'll need 240 as well I guess. What size wire would I need to do this? Also, would expect to have 100 amp subpanel, I guess.
Thanks

jhesse
Apr 8, 2009, 04:26 PM
I have decided to go with 6/3 with ground. I believe this should be sufficient. Thoughts?

stanfortyman
Apr 8, 2009, 05:34 PM
#6cu at that distance will give you about 50 amps max before voltage drop is a concern.

This should be fine unless the welder you are considering is a typical stick welder.

Missouri Bound
Apr 8, 2009, 08:07 PM
#6 to a 100 amp sub panel?. NO CAN DO..

stanfortyman
Apr 9, 2009, 06:17 AM
#6 to a 100 amp sub panel???....NO CAN DO..What does the size of the panel matter? When was the last time you saw a 12, 16, 20, etc, space panel rated less than 100A?

As long as the feeder breaker is proper #6 is perfectly fine, and very commonly used as a sub-feeder.

stanfortyman
Apr 9, 2009, 06:19 AM
For a FULL 100A (80A continuous) feeder you'd need #4cu or #3cu in this case.

jhesse
Apr 9, 2009, 08:31 AM
Yeah, I realize #6 is 60 amp, but I thought I could still use a 100 amp panel box. Do you guys think I would be better to go with #4? Thanks for your imput.

stanfortyman
Apr 9, 2009, 08:50 AM
You CAN use a 100A panel. If you go with#4 you can use a 70 or 80A breaker.

brotzmr
Apr 9, 2009, 10:24 AM
2/3 wire is rated up to 95 amps.do you no the nec codes for your area. Some require a circuit breaker if your running 6 circuits or more from your sub-panel

Missouri Bound
Apr 9, 2009, 07:12 PM
I assumed ( out of U and ME) that you intended to use a 100 amp breaker in this 100 amp panel. But whatever main you use will dictate the size of the wire, as Stan eluded to. :)

KISS
Apr 9, 2009, 07:20 PM
The main doesn't dictate the size of the panel, the feeder breaker does. The main in the sub could be 100 A with a 60 Amp feed breaker. In this case the 100 A breaker is just a disconnect.

Reminder: 130' sounds like the shop is in a detached structure. If it is a ground rod is required.

jhesse
Apr 9, 2009, 07:30 PM
Yeah, it is detached, and there is already a ground rod in place. I bought the place and they had service out there, but it was overhead, and when it went into the shop, they had 3 of the outdoor style shutoffs with the fuses. I don't like it, and want to modernize. It was built in 67, and they just kept adding on as they needed. Thanks for all your guys' help.

donf
Apr 10, 2009, 07:00 AM
Brotzmr,

Could you please explain this quote for me?

"2/3 wire is rated up to 95 amps.do you no (know?) the nec codes for your area. some require a circuit breaker if your running 6 circuits or more from your sub-panel"

You have to have a breaker to protect the feeder circuit from the panel. At the subpanel, you cannot have more than six switches (breakers). However, you can have a master cut off switch or a main breaker to cut the power in an emergency.

NEC is National or International set of electrical codes, not local. Local governments may have codes that change or modify the NEC codes.

What kind of 2/3 wire are you talking about? What insulation do you think should be on the wire? Have you looked at the NEC and noticed that #4 AWG is used for 100 amp feeder circuits?

Missouri Bound
Apr 10, 2009, 05:18 PM
Lets get past the semantics... JHESSSE... is it your plan to have a 100 amp service in this shop? I based my comments on that, and just wondering if that is indeed the case, or I speculated wrongly. With the lighting and outlet load you want, and the compressor and welder usage you probably don't need a 100 amp service, unless the shop will be used by a few people at a time and the equipment will be operated simultaneously. Only you know that.

jhesse
Apr 13, 2009, 10:15 AM
No, not necessarily 100 amp. Was just going to get a panel rated for 100 amps. Sorry for the confusion.