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Multiple Fire Pumps / Single Circuit

Merry Christmas

NSHHS

Member
Location
Japan
Occupation
US Military Hospital Contractor
Team,
After a lot of digging I'm not coming up with a clear answer. Hoping someone can assist.

Q: Can 2 fire pumps (or FP controller, ATS,) be on the same circuit breaker or should they have independent breakers.

INFO:
- My pumps are separate function (1 feeds hose stands, 1 feeds sprinklers). I know you want as few items inline that can break in the event of a fire.
- My pumps are fed by a single commercial breaker and single emergency breaker from the generators.
- Each pump has a dedicated ATS/controller

My thought is that you don't want a single breaker failing and taking out both pumps. Because during our annual FP test (run pumps and simulate commercial power loss, test ATS and breakers).....the EM breaker failed during transfer and both pumps failed to turn back on. Going to replace the breaker but it raised a question in my brain...

Thanks in advance, Neil
 

NSHHS

Member
Location
Japan
Occupation
US Military Hospital Contractor
How would you even size a single circuit to two pumps?
I know. So the building was built originally with only hose stands. In ‘95 they sprinklered the facility and that’s where I assume the single circuit tie in occurred. It’s a mess and I find something new daily.
 

Ohm2

Member
Location
Washington
Occupation
Electrician
I’m thinking NEC 695
Wait on others I’m no guru on fire pumps, but below is what I believe each code means:
1. NEC 695.3(A)
- This section specifies that fire pumps must have a reliable power supply. It does not allow overcurrent protection devices that could inadvertently shut off power to a fire pump unless they are specifically designed to handle the fire pump load.

2. NEC 695.4(B)(2)(a)
- Fire pumps must have a dedicated connection from the source of power, and if using a circuit breaker, that breaker must be specifically for the fire pump. This means that each fire pump must be served by its own OCPD, and the circuit feeding a fire pump cannot serve any other loads.

3. NEC 695.4(B)(3)
- If additional power sources are used (like emergency generators), the fire pump must have its own connection, meaning the emergency power cannot serve multiple fire pumps through the same breaker.
 

NSHHS

Member
Location
Japan
Occupation
US Military Hospital Contractor
Wait on others I’m no guru on fire pumps, but below is what I believe each code means:
1. NEC 695.3(A)
- This section specifies that fire pumps must have a reliable power supply. It does not allow overcurrent protection devices that could inadvertently shut off power to a fire pump unless they are specifically designed to handle the fire pump load.

2. NEC 695.4(B)(2)(a)
- Fire pumps must have a dedicated connection from the source of power, and if using a circuit breaker, that breaker must be specifically for the fire pump. This means that each fire pump must be served by its own OCPD, and the circuit feeding a fire pump cannot serve any other loads.

3. NEC 695.4(B)(3)
- If additional power sources are used (like emergency generators), the fire pump must have its own connection, meaning the emergency power cannot serve multiple fire pumps through the same breaker.
I was interpreting these the same way. I might have to contact a buddy who’s NICET certified for fire system design and get his take.
 
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