Replies

1. 
   IMERC | Jul 19, 2003 09:08pm | #1

   Lay a new pipe. Easier. More $.

   If you chose to add the new conductors to the exsisting conduit, up grade the ground (#10). Drop the exsisting ground (#12). Pull the the old wires and when you pull the new run repull the 12's. Pulling wire on top of wires can very easly damage the insulation. You can ceate some serious problems.

1. 
   MisterT | Jul 19, 2003 10:06pm | #2

   Thanks IMERC!

   Methinks I will add a 10 to the old pipe and repull the 12's.

   so 3 12's and 3 10's should pull thru OK?

   I guess I'll find out!!

   Tanks again.

   Mr T

   Do not try this at home!

   I am an Experienced Professional!

1. 
   pm22 | Jul 19, 2003 10:09pm | #3

   You can pull in #12 red, #12 green, #10 black and #10 white.

   Use wire pulling lubricant.

   If you pull all the wires out, attach a string to the end first.

   ~PeterView Image

2. 
   IMERC | Jul 19, 2003 10:45pm | #4

   More to think about.

   You leaving out the ground? Hope not. #12 for ground will work. Some municipalities won't allow it and you will have to go with a #10. I would.

   Red / Black #12's. Warning flag says it might be a 220v line 4 wire application. What do the 12's service? Wiring configuration says that it could be split 110v also. A single neutral for two 110v circuts is cool. In a 4 wire application they stay as is. A single ground for both is fine.

   As for space in the tube... You'll have room to spare.

3. 
   pm22 | Jul 20, 2003 02:41am | #5

   Mr. T,

   Refering to your 3rd post, it now seems that you wan to add a 3rd circuit instead of enlarging one of the original circuits.

   That would mean #12 black, #12 red and #12 white. That's for the two original circuits. Then #10 white and #10 black for the new larger circuit. The green #12 should suffice for the ground for all three circuits.

   "so 3 12's and 3 10's should pull thru OK?" This looks like you want to go with a #10 ground. It's a bit harder to pull in PVC than EMT but you only have 25'. How many bends in the conduit and where are they located? [That is, a horizontal 90º which immediately leads to a vertical 90º is hard to fish through.]

   ~PeterView Image

2. 
   4Lorn2 | Jul 20, 2003 05:31am | #6

   I would yank out one of the #12 grounds and use the second to pull in your three, two hots and a ground, for the new circuit. Sharing the ground on the load end, and on to the panel, is fine. Make a nice tight smooth head. Use plenty of lube and have someone feed it as you pull. Tearing up existing wires in a conduit by pulling in new ones is possible but on such a short run, with modern insulation and with a conduit with plenty of room I would go for it without any great trepidation.

   You could pull everything out and refeed it but IMHO this often is more Murphoid than it sounds. Laid out wired get stepped on. Wires pulled out tend to bloom and tangle. Any of the insulation can be damaged when being pulled in. Especially when they are distorted and fighting you. At the least it takes a lot more time.

   I see this situation a lot.

3. 
   Luka | Jul 20, 2003 06:09am | #7

   Run a new pipe.

   You wont regret it in the future.

   A good heart embiggins even the smallest person.

   Quittin' Time

1. 
   4Lorn2 | Jul 21, 2003 03:30am | #8

   At first I was kind of thinking along the same lines because in these situations it is not uncommon for people to keep adding circuits. He can get the 30A circuit in today but adding more might be more of a problem. A second conduit, if it wasn't made too difficult to install by the situation would, make any future additions easier. Always a good thing.

   Of course with two three-wire circuits and a 30A 240v he is getting pretty close to being better off with a subpanel.  I think a subpanel is the way to go for a shop. A simple 60A panel would likely do the job, be easy to pull into the existing conduit and save leg work in the long run. Having a panel in the shop makes correcting a tripped breaker less trouble. Also it makes adding circuits a breeze. Except for multi-man production or commercial shops I can't recall, off the top of my head, any shops that needed more than 60A at any one time.

1. 
   Luka | Jul 21, 2003 03:51am | #9

   Exactamentaly !!!

   Best choice of all.

   A good heart embiggins even the smallest person.

   Quittin' Time

1. 
   edlee516 | Jul 21, 2003 04:12am | #10

   um..........yeah and pretty much required by the NEC when you are bringing power to an outbuilding.

   Ed