Question on 695.3(A)(3) (2020 edition) - Dedicated Feeder to Fire Pump

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nhee2

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I am confused by what is meant by this section. It allows a normal power source to an electric fire pump to be 'a dedicated feeder....derived from a service connection as described in 695.3(A)(1).

Is this saying a dedicated feeder from a separate service connection that is intended for a fire system? A dedicated feeder from a normal service, but installed with the protection from fire hazards described in 695.3(A)(1).

I am frequently seeing designs in industrial facilities with fire pumps fed from 'normal' MCC or switchboard lineups, and I do not see how they are compliant with 695, unless somehow 695.3(A)(3) applies to that type of installation.

Can anyone explain the intended configuration described in that section?
 
I’ve seen 695.3(A)(3) applied to fire pumps served via 695.3(A)(1) but thru a dedicated service disconnecting means with overcurrent protection meeting 695.4(B).

The fire pump is connected on the load side of the service overcurrent protection and becomes a dedicated feeder.

To do what is being described in your post requires compliance with 695.(3)(C).
 
JoeStillman said:
Exhibit 695.3 in the handbook illustrates what they're talking about. If you're connected downstream of a service disconnect, you're not compliant with 695.3(A)(3).
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In the 2020 Handbook? If yes - I see both of those diagrams describing 695.3(A)(1) configurations, and not 695(A)(3).
 
nhee2 said:
I am confused by what is meant by this section. It allows a normal power source to an electric fire pump to be 'a dedicated feeder....derived from a service connection as described in 695.3(A)(1).

Is this saying a dedicated feeder from a separate service connection that is intended for a fire system? A dedicated feeder from a normal service, but installed with the protection from fire hazards described in 695.3(A)(1).

I am frequently seeing designs in industrial facilities with fire pumps fed from 'normal' MCC or switchboard lineups, and I do not see how they are compliant with 695, unless somehow 695.3(A)(3) applies to that type of installation.

Can anyone explain the intended configuration described in that section?
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That's not code compliant. It has to be a physically separate section, tapped ahead of any service disconnect, and it has to be clearly labeled for its purpose.
 
JoeStillman said:
695.3(A)(3) points you back to 695.3(A)(1)...
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Right - so I was unclear as to what a dedicated feeder on a service derived from 695.3(A)(1) was. Looking at the diagram in the handbook - if a service disconnect is added, then does the circuit become a feeder, and that's what they are talking about? Or - a service which feeds several fire pumps, so that there are individual feeders from the single service?
 
Service Conductors. The conductors from the service point to the service disconnecting means.
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If your fire pump circuit is fed from a point between the meter and the non-fire-pump service disconnect, then it is a service and the fire pump disconnect (usually part of the starter) is a service disconnect. That is one reason why that circuit has to be outside the building or use a fire-rated wiring method - it is a circuit with no upstream overcurrent protection.
 
JoeStillman said:
If your fire pump circuit is fed from a point between the meter and the non-fire-pump service disconnect, then it is a service and the fire pump disconnect (usually part of the starter) is a service disconnect. That is one reason why that circuit has to be outside the building or use a fire-rated wiring method - it is a circuit with no upstream overcurrent protection.
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Yeah. I get that. 695.(A)(3) is talking about a feeder, not a service. That is what i do not get, or am asking what is the typical config. I guess post #2 is the answer.

Thanks,
 
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