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Posted By: cgw Fire Pump Service - 12/14/05 03:14 PM
Quesion on the installation of the service feeder to a fire pump:
The fire pump feeder is connected to the service at the meter before the building main disconnect. The feeder is connected to the fire pump control panel (and disconnect) which is in a remote location from the electric service (there is no disconnect for the fire pump at the service location). So far so good?
Does the feeder for the fire pump need to follow the rules for the installation of a service to the remote location? In other words does it need to be protected by concrete or can it just be run through the building?
Posted By: gfretwell Re: Fire Pump Service - 12/14/05 03:23 PM
If you get the names of the conductors right you have your answer. Conductors on the line side of the first means of disconnect are service conductors. They can't be inside the building. 2" of concrete gets them "outside".
If this was really a feeder, (on the load side of the disconnect<s> ) it would be OK in the building
Posted By: cgw Re: Fire Pump Service - 12/14/05 07:59 PM
Looking at Article 695 it looks like my only option is to either run the conductors outside the building or under the floor slab to the fire pump. In my case it would be easier to run outside the building I think.
The service comes in at one end of the building (the meter is inside the building in an electric room). The "service" for the fire pump is connected to the meter before the main disconnect (circuit breaker). The fire pump "service" will be instaled in conduit out the wall and along the outside of the building to the fire pump room (which is at the other end of the building). The disconnect and circuit breaker for the fire pump are at the fire pump.
Anything wrong with this scenerio?
Posted By: gfretwell Re: Fire Pump Service - 12/14/05 08:43 PM
I had a situation where they needed to stay "outside" in the building. They formed up a curb along the floor to wall joint with 2x6s, dropped in a 2" and poured it solid with concrete. That gave them about 2" of concrete over the pipe.
Posted By: jes Re: Fire Pump Service - 12/16/05 08:39 PM
cgw, I would consult with whoever is the AHJ here for the fire pump installation. They MAY have a position on tapping the building service for the fire pump (common service) and the physical location of the service (running the entire building length. It may ber different than what the Code permits you to do as a minimum.
Posted By: trekkie76 Re: Fire Pump Service - 12/18/05 01:00 AM
Looks like in 695-6a they want it outside of the bldg. Also, remember to have the service for the fire pump in a seperate enclosure from the regular service. It is also allowed to have another service put on the bldg for a special application. Don't know if it would help any in your situation.
Posted By: iwire Re: Fire Pump Service - 12/18/05 01:06 AM
Quote
Looks like in 695-6a they want it outside of the bldg

Yes bu we have to understand what the NEC means when it talks about conductors outside of the building.

Quote
230.6 Conductors Considered Outside the Building.

Conductors shall be considered outside of a building or other structure under any of the following conditions:

(1)Where installed under not less than 50 mm (2 in.) of concrete beneath a building or other structure

(2)Where installed within a building or other structure in a raceway that is encased in concrete or brick not less than 50 mm (2 in.) thick

(3)Where installed in any vault that meets the construction requirements of Article 450, Part III

(4)Where installed in conduit and under not less than 450 mm (18 in.) of earth beneath a building or other structure
Posted By: trekkie76 Re: Fire Pump Service - 12/18/05 01:29 AM
I was under the impression that if something was physically outside the building, it was in fact considered as such. In 230-6, I interperted that as if you had to run through a bldg, to keep it "outside " the bldg, you encased it in 2" of concrete,in a vault, or in conduit under 18" of earth under the bldg.

So, you are saying that because the code says under these conditions conductors are considered outside, that if they physically are outside, but don't meet the conditions in 230-6, they really are not?
Posted By: cgw Re: Fire Pump Service - 12/18/05 02:07 PM
In my case the meter is inside the building so I have to have a few feet at least in the building before it goes back out (to the fire pump).
To address the post of jes above - in this city I do not think the AHJ will look at the electric. The city building department will not look at it and the fire marshall will not look at the electric. The only one that may say anything is the underwriter inspector.
Posted By: Bob Re: Fire Pump Service - 12/18/05 11:43 PM
230.6 Conductors Considered Outside the Building.
Conductors shall be considered outside of a building or other structure under any of the following conditions:

(1)Where installed under not less than 50 mm (2 in.) of concrete beneath a building or other structure

This covers conductors beneath the building.

(2)Where installed within a building or other structure in a raceway that is encased in concrete or brick not less than 50 mm (2 in.) thick

This covers conductors within the building.

(3)Where installed in any vault that meets the construction requirements of Article 450, Part III

Covers conductors in a vault.

(4)Where installed in conduit and under not less than 450 mm (18 in.) of earth beneath a building or other structure

Covers conductors beneath the building.

If your conductors are actually "physically outside of the building" then the above statements do not apply.
I would like to know what size is the pump, conductor size and how long a run would you have to install.




[This message has been edited by Bob (edited 12-18-2005).]
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