jph320 Posted July 15, 2010 Report Posted July 15, 2010 i am running a 200 amp service which needs tobe in conduit. Can I run EMT to a rigid LB with a rigid nipple to another rigid LB to go through the wall and then back to EMT again?
Marc Posted July 15, 2010 Report Posted July 15, 2010 I don't see an issue with the double change in methods (emt/rigid and vice versa) but I'm guessing that you'll have a problem getting 3 #2/0 through the 2 LB's especially when they are separated only by the thickness of a wall. I'd look for another route or consult with the counterman at your electrical wholesaler. Marc
jph320 Posted July 15, 2010 Author Report Posted July 15, 2010 This is for an auto body shop so I was pulling 4/0 in a 2in conduit. by the way it is 3 phase.
Marc Posted July 15, 2010 Report Posted July 15, 2010 I don't think you can do it. If you've got muscles like ropes in your forearms and you fight it, you might get the cover on the LB's but I'd be worried about damage to the insulation and arcing later on. Arcing on a service entrance conductor prior to the main breaker is arrested only by the utility fuse, which is usually a super lag. If it arcs, it may vaporize considerable metal before it's over and a big part of the immediate neighborhood will hear it. It's not safe to proceed on this plan and you should not do so. I'm assuming that you are a licensed electrical contractor. Marc
jph320 Posted July 15, 2010 Author Report Posted July 15, 2010 Yes I am Licensed. I am just new to the commercial end. I did residential for 15 years and now I am going after the bigger fish. I might then try an LB followed by a sweep 90. what do u think?
Marc Posted July 15, 2010 Report Posted July 15, 2010 That helps, but I still wouldn't even consider it. Give yourself a wider margin of safety, at least until you get more experience. Try 3" conduit with a large LB. Some have more volume than others. Chk if you've a 3" knockout on the meter box or CT box. Marc
jph320 Posted July 15, 2010 Author Report Posted July 15, 2010 Well couldn't i just use ser cable on the outside? From the weather head along the wall to a hole in the cinder block then to a sweep 90 and then down the inside wall to the socket.? The run will be about 12ft from the ground outside and i could do without the conduit. 2in emt will hold 4 4/0 aluminum wire(3 hots and a neutral) as per the code book. I would just use it inside the shop to protect it
Jim Katen Posted July 15, 2010 Report Posted July 15, 2010 i am running a 200 amp service which needs tobe in conduit. Can I run EMT to a rigid LB with a rigid nipple to another rigid LB to go through the wall and then back to EMT again? Go here: http://forums.mikeholt.com/forumdisplay.php?f=65 - Jim Katen, Oregon
wirenut1110 Posted July 24, 2010 Report Posted July 24, 2010 I realize this post is old however, you mention 4/0 AL. 310.15(B)(6) only applies to single phase dwelling services. You would need to use 250 MCM(kcmil) aluminum or 3/0 copper.
branover Posted July 27, 2010 Report Posted July 27, 2010 I agree. It seems like it would be MCM wire used for a large service for commercial use. But I suppose it also depends on the load calc and what service planning wants. http://www.branovercontractors.com http://www.branovercontractors.com
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now