3 phases in different conduits

Status
Not open for further replies.
W

wire monk

Member
what is the code section that say's phases can be in different pipes if they are bundled together. All the A phases in one pipe all the B phases in one pipe and all the C phases in another pipe. I was told it is in the new code....
 
wire monk said:
what is the code section that say's phases can be in different pipes if they are bundled together. All the A phases in one pipe all the B phases in one pipe and all the C phases in another pipe. I was told it is in the new code....
Click to expand...

Not new, but pretty darn limited in application.

See the exception to 300.4(B)(1)
 
It is a restrictive type of installation, because when installed incorrectly, it goes bad in a bad way.


Also, be aware that many utility companies do not like to approve this type of installation anymore, even if the NEC does. Make sure to talk to them and get it in writing.
 
Pierre C Belarge said:
It is a restrictive type of installation, because when installed incorrectly, it goes bad in a bad way.


Also, be aware that many utility companies do not like to approve this type of installation anymore, even if the NEC does. Make sure to talk to them and get it in writing.
Click to expand...

I would have to agree with this 100%.
 
*music* I heard it through the grape vine *end music*

*music* I heard it through the grape vine *end music*

I have heard of instances where services have been ripped apart due to the magnetic forces involved in high current draws with each phase having it's own dedicated conduit.

Even if approved this type of installation is not for the weak of nerves.
 
If done correctly, using the code exceptions, each conduit will become a great on site cooking facility, just bring ferrous pots and sit them close to the raceway. Inductive cooking is the big rage in high end kitchens, and you'll have one for free.
 
I believe you could install the feeders in the way described as long as they were pulled into PVC conduit. You would also need enter the switchgear from the bottom like a duct bank so that there would not be any metal encircling the PVC conduits. Samething applies to the other end of the conduit run...no metal encircling the conduits. No metal bushings either(although I don't why anyone would put a metal bushing on the end of a PVC conduit unless they were worried about damaging the conduit during the installation of the feeder conductors.)
 
Red Wiggler said:
I believe you could install the feeders in the way described as long as they were pulled into PVC conduit. You would also need enter the switchgear from the bottom like a duct bank so that there would not be any metal encircling the PVC conduits. Samething applies to the other end of the conduit run...no metal encircling the conduits. No metal bushings either(although I don't why anyone would put a metal bushing on the end of a PVC conduit unless they were worried about damaging the conduit during the installation of the feeder conductors.)
Click to expand...


You certainly could enter the conduits through a non-ferrous metal. This is SOP for MI cable terminations when each conductor is run in a separate cable.
 
Fulthrotl said:
i'll see your 100% and raise you another 100%.

why would you want to do such a thing? what benefit is there?
Click to expand...

As emahler says, terminating. It is much easier to keep cable lengths the same using this method and keeps the inside of the gear much less cluttered/congested not having to cross conductors. This really makes a difference when you get to (4) or more sets.


Roger
 
Als_Isolated_Phase.JPG
 
Status
Not open for further replies.
Top