Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
Quote:
You ever gotten whacked with the 500 or 600 mcm? HE HE HE, hurts like HE**!
Oh yeah, do not let it fall on you feet either. 
Hi guys, this is an unfair question if you have not worked with parallel conductors.
I certainly would not know the answer either if I did not deal with them frequently.
Brown, orange and yellow, are the local "standard" (not a code) for 480 volts, if you could see the neutral it is marked gray, that is a MA code for a 480 volt neutral.
No grounding conductor needed, just as there is no grounding conductor for house service conductors, hots and neutral only.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Bob Badger wrote:
Hi guys, this is an unfair question if you have not worked with parallel conductors.
I certainly would not know the answer either if I did not deal with them frequently.
Brown, orange and yellow, are the local "standard" (not a code) for 480 volts, if you could see the neutral it is marked gray, that is a MA code for a 480 volt neutral.
No grounding conductor needed, just as there is no grounding conductor for house service conductors, hots and neutral only.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Looks like that meets the Exception as stated in 300.3 (B) (1) Exception, but cannot tell for sure. Are the raceways nonmetallic?
300.3 Conductors.
(B) Conductors of the Same Circuit. All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord, unless otherwise permitted in accordance with 300.3(B)(1) through (4).
(1) Paralleled Installations. Conductors shall be permitted to be run in parallel in accordance with the provisions of 310.4. The requirement to run all circuit conductors within the same raceway, auxiliary gutter, cable tray, trench, cable, or cord shall apply separately to each portion of the paralleled installation, and the equipment grounding conductors shall comply with the provisions of 250.122. Parallel runs in cable tray shall comply with the provisions of 392.8(D).
Exception: Conductors installed in nonmetallic raceways run underground shall be permitted to be arranged as isolated phase installations. The raceways shall be installed in close proximity, and the conductors shall comply with the provisions of 300.20(B).
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Joe,
You are REQUIRED to have one of each phase conductor and a neutral in each raceway, when using parallel conductors, with the one exception of that Exception (stated above).
Cuts down on unwanted and undesirable magnetic fields and eddy currents, etc.
You will notice that the Exception is very specific and very limited too.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
A, B, C, plus neutral.
Next conduit gets another A, B, C, plus a neutral.
So does the next, etc., depending on how many parallel conductors you have. I've never worked on anything like Bob did in that photo he posted.
My Dad was an electrical contractor and he mostly did residential with some light commercial, and only a couple of larger industrial jobs when I worked with him. After that I was strictly into residential stuff with a little light commercial stuff. Then out of it.
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
This could just as easily apply to a 400 amp+
single phase home service.
The contractor might run two sets of 200 amp
conductors, in that case in each raceway
should be phase A, B, & N
If you where to see any other combination like
A, A, N in one pipe and N, B, B in the other,
FLAG it, the pipes (if not PVC) will get hot
even with PVC pipes the metal enclosures will
get hot where the wires pace through like this.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Bob,
I was referring to more than two parallel conductors. I run into that occasionally, but they are not too large to bend, so they are run the 'typical' way.
The exception would not likely be applied to residential work as they must run underground, and, at least down here, that would be to the exterior disconnect, or an interior disconnect on the inside of the garage wall. Thus, the 'underground' part would not apply, and the exception would not apply.
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
Jerry that was not specifically aimed at you.
I do agree with you that the exception has
a very limited usage and I do not see how it
could be applied to a residence.
My point was only if any of the HIs that open
panels keep an eye out for this.
For 400 amps we do not usually go to parallels
get to 600 amps and we are likely to break it up. 
