Fire pump feeder

[STRUT12034]

What is considered a 2 hour rated form of protecton for a fire pump feed that is being fed from a transformer outside of the building and then entering into a building and continuing 20' exposed, can this just be rigid conduit?

 

[Npstewart]

I believe you have to use type RHW-2 cable. A lot of manufacturers have their own trade name for this but if you search RHW-2 you will probably find what you need. Just make sure it has a rating of 2 hours and it would be wise to run this by the fire marshall and get his written approval. The fire pump is about as useful as a toaster at putting out a fire if you cant get power to it.

 

[jrohe]

What is considered a 2 hour rated form of protecton for a fire pump feed that is being fed from a transformer outside of the building and then entering into a building and continuing 20' exposed, can this just be rigid conduit?

If these are conductors between the utility transformer and the fire pump controller, are these not considered service conductors? If they are, they are subject to NEC section 695.6(A)(1), which requires the conductors to be installed either outside the building or installed in accordance with 230.6(1) or (2). NEC section 230.6(1) requires the conductors under not less than 2 inches of concrete beneath a building while 230.6(2) requires the conductors to be encased in a minimum of 2 inches of concrete or brick.

 

[Gregg Harris]

If these are conductors between the utility transformer and the fire pump controller, are these not considered service conductors? If they are, they are subject to NEC section 695.6(A)(1), which requires the conductors to be installed either outside the building or installed in accordance with 230.6(1) or (2). NEC section 230.6(1) requires the conductors under not less than 2 inches of concrete beneath a building while 230.6(2) requires the conductors to be encased in a minimum of 2 inches of concrete or brick.

I would agree 695.6 is the answer

 

[infinity]

There was a time when you could use 2 hour listed conductors but recently those conductors lost their listing.

 

[RB1]

JRohe has raised a good point regarding the routing of service conductors through the building. If these are service conductors (depends on who owns the transformer and where the service point is) you need to comply with 695.6(A). If these are feeders conducors you may not need additional protection if the 20 feet of conduit is located within the fire pump room.

 

[texie]

There was a time when you could use 2 hour listed conductors but recently those conductors lost their listing.

Yes and I believe that is UL "FHIT". It seems at this point the loss of the listing now only applies to pipe and wire systems. MI cable has been reinstated. Of course as others pointed out, this may be a moot point if the OP has service conductors.
Another interesting part of FHIT using pipe and wire (when it was approved) is that there are a number of other requirements that had to be met for it to be a valid 2 hour rating. For starters, you could not use it in a wood frame situation as the framing may collapse in a fire. The fire rating of the FHIT assembly would be lost due to it falling down.