Fire Pump Overcurrent Protection

[PcolaEE]

NEC 230.90 Requires overload protection for "Each ungrounded service conductor".
Exception No 4 states that for fire pump supply conductors, this shall comply with 695.4 (B)(2)(a).
The problem I am running into, is that the breaker in a SUSE rated fire pump controller does not meet the requirements in NEC 695.4 (B)(2)(a). If that is the case, would I not need an overcurrent protection device ahead of every fire pump controller? If not, can someone point me to the code which states that this is not required or why my assumptions are incorrect? I have checked with multiple manufacturers and they all indicated that the breakers in their controllers DO NOT meet the requirements in NEC 695.4 (B)(2)(a).

 

[gadfly56]

NEC 230.90 Requires overload protection for "Each ungrounded service conductor".
Exception No 4 states that for fire pump supply conductors, this shall comply with 695.4 (B)(2)(a).
The problem I am running into, is that the breaker in a SUSE rated fire pump controller does not meet the requirements in NEC 695.4 (B)(2)(a). If that is the case, would I not need an overcurrent protection device ahead of every fire pump controller? If not, can someone point me to the code which states that this is not required or why my assumptions are incorrect? I have checked with multiple manufacturers and they all indicated that the breakers in their controllers DO NOT meet the requirements in NEC 695.4 (B)(2)(a).

It is generally agreed that the conductors to fire pumps are treated as service conductors all the way to the controller or ATS, if there is one. The rules for an OCPD ahead of the controller are different from the rules for what is inside the controller. You may, but are not required to, have a disconnecting means ahead of the controller. That is where the locked rotor requirement comes in, NOT inside the fire pump controller.

 

[PcolaEE]

Thank you for the response. I don’t disagree with you. I just cannot find anything in the code that allows us to do that if you go to the exception for 230.90 it takes you straight to 695 requirements for overload protection. I believe it’s 230.90 exception number three.

 

[david luchini]

Thank you for the response. I don’t disagree with you. I just cannot find anything in the code that allows us to do that if you go to the exception for 230.90 it takes you straight to 695 requirements for overload protection. I believe it’s 230.90 exception number three.

That's an interesting one because the installation you describe doesn't fall under 695.4(B)...it falls under 695.4(A).

What size is the fire pump and what size is the C/B in the controller?

 

[PcolaEE]

That's an interesting one because the installation you describe doesn't fall under 695.4(B)...it falls under 695.4(A).

What size is the fire pump and what size is the C/B in the controller?

I agree with that too but 230.90 says you have to have overload protection and exception 4 takes you to 695.4 (B). That's really where my confusion is. There are no other options per 230.90. Its almost like 695.4(A) contradicts 230.90.

As far as the breaker size goes, the manufacturer told me very clearly that the breaker in the controller does not ever meet the requirements in 695.4 (B) which makes sense.

 

[david luchini]

I agree with that too but 230.90 says you have to have overload protection and exception 4 takes you to 695.4 (B). That's really where my confusion is. There are no other options per 230.90. Its almost like 695.4(A) contradicts 230.90.

As far as the breaker size goes, the manufacturer told me very clearly that the breaker in the controller does not ever meet the requirements in 695.4 (B) which makes sense.

Looking at a couple of Fire Pump Controller manufacturers, it looks like they comply with 695.4(B)(2)(a).

They all comply with NFPA 20 which says it either has to carry the locked rotor current indefinitely, or have alternative compliance of given trip times for given overcurrent levels.

Seems to me, per NFPA 20 they follow the requirements of 695.4(B)(2)(a) then they meet the requirements of the 230.90 exception.
And if the follow the alternative compliance, then the meet the requirement of having overload protection per 230.90.

 

[PcolaEE]

Looking at a couple of Fire Pump Controller manufacturers, it looks like they comply with 695.4(B)(2)(a).

They all comply with NFPA 20 which says it either has to carry the locked rotor current indefinitely, or have alternative compliance of given trip times for given overcurrent levels.

Seems to me, per NFPA 20 they follow the requirements of 695.4(B)(2)(a) then they meet the requirements of the 230.90 exception.
And if the follow the alternative compliance, then the meet the requirement of having overload protection per 230.90.

Unfortunately I have discovered over the past week that two of the manufacturers I contacted directly (Eaton and Hubbell) do not meet the requirements in 695(B)(2)(a). That's the reason I started this thread. There's either a disconnect between controller manufacturers and NEC requirements or I am just reading the code wrong. I honestly wish someone would tell me that I am reading the code wrong.

 

[david luchini]

Unfortunately I have discovered over the past week that two of the manufacturers I contacted directly (Eaton and Hubbell) do not meet the requirements in 695(B)(2)(a). That's the reason I started this thread. There's either a disconnect between controller manufacturers and NEC requirements or I am just reading the code wrong. I honestly wish someone would tell me that I am reading the code wrong.

I don't believe they're required to meet 695.4(B)(2)(a), as 695.4(A) applies.

If you were to provide overcurrent upstream of the controller, that would have to meet the requirements of 695.5(B)(2)(a).

 

[PcolaEE]

I don't believe they're required to meet 695.4(B)(2)(a), as 695.4(A) applies.

If you were to provide overcurrent upstream of the controller, that would have to meet the requirements of 695.5(B)(2)(a).

right but 695.4(A) doesn't comply with 230.90 and every service needs to comply with 230.90

 

[david luchini]

right but 695.4(A) doesn't comply with 230.90 and every service needs to comply with 230.90

But it does comply with 230.90...per the requirements of NFPA 20.