I am currently designing around an existing fire pump installation to include an alternate source (generator). This is new code area for me and would appreciate any comments, challenges, or suggestions anyone may have.
Context
An industrial facility desires to connect a generator to an existing fire pump application. Currently, a single 150 hp fire pump motor and 1.5 hp jockey pump controller is installed and located within a stand-alone pump house that is remote from the main plant. A walk down has revealed the electrical supply originates within switchgear located in an electrical room inside the plant and is supplied from an unmarked 600A low-voltage breaker located in a vertical section of switchgear with other breakers feeding industrial loads. The circuit routes leaves the room and routes underground to the stand-alone pump house and directly feeds an 800A distribution panel. The fire pump controller is then fed from a thermal-magnetic breaker located within the distribution panel. The distribution panel also feeds jockey pump and non-fire protection related loads (e.g., site lighting circuits).
Code Applicability
The local jurisdiction does not have an electrical inspector or fire marshal. However, a reasonable standard of care for electrical engineering design would seem to indicate that the NEC and NFPA 20 electrical requirements would nevertheless apply to the design and installation.
Does anyone have a differing view?
Are these legitimate code deficiencies in the existing configuration?
Reading 695 it seems (emphasis on seems) to indicate the existing configuration has code deficiencies listed below. Please note Code references are taken from NEC – 2020, Handbook.
(1) 695.3(A)(1), which requires a connection located ahead of (but not within) the service disconnecting means.
Reason: The connection is originates from a breaker within switchgear; it does originate ahead of the service disconnecting means.
(2) 695.4(B)(3)(a)(3), which prohibits a disconnecting means from being located within the same enclosure that supplies loads other than fire pump.
Reason: If the 600A breaker can legitimately function as disconnecting means, it cannot be located in the same switchgear section with breakers that supply industrial loads. This deficiency seems to apply both for the 600A breaker located in the switchgear inside the facility as well as the thermal-magnetic breaker located in the distribution panel in the pump house that feeds the fire controller.
(3) 695.4(B)(1)(a), which requires single disconnecting means and OCPD between the power source and the listed fire equipment.
Reason: Upstream of the listed fire controller, there are two disconnecting means installed: the 600A breaker and the thermal magnetic breaker in the local distribution cabinet.
(4) 695.4(B)(2)(a)(1), which requires overcurrent protection sized in accordance with locked rotor current of the fire pump.
Reason: The 600A breaker in the switchgear and thermal-magnetic breaker in the local distribution panel are not sized to tolerate the LRC of both the fire pump and jockey pump indefinitely. This conclusion is based on LRCs contained in T.430.251(b).
(5) 695.4(B)(3)(a), which requires the disconnect means to be suitable for use as service equipment and lockable in the closed position.
Reason: The breaker is currently not able to be locked in the closed position. This seems to apply to both breakers in the fire pump power circuit.
(6) 695.4(A), which requires the supply conductors to directly connect the power source to a listed fire pump controller, a listed combination fire pump controller and power transfer switch, or a listed fire pump power transfer switch.
Reason: The fire pump supply conductors do not directly terminate into a fire listed device, they terminate into a non-fire listed distribution panel within the pump house.
Remediation/ Generator Design Questions
By installing a generator it appears that the apparent code deficiencies above would need to be remediated along with a code compliant generator design.
(1) Am I correct in thinking the existing “normal supply” circuit would need to be re-configured such that “dedicated feeder [695.3(A)(3)]” is derived from a connection ahead of the service disconnecting means or derived from a direct connection to a transformer’s secondary terminals?
(2) Am I correct in thinking that the normal-supply “dedicated feeder” would need to have a direct connection to the fire pump controller such that when the circuit emerges into the pump house it only feeds the fire pump controller (and a jockey pump connection permitted if made in accordance with a Type 2 junction box [695.6(I)])?
(3) Does NEC 695.6(E) prohibit a listed fire ATS from feeding a distribution panel that would contain jockey pump as well as non fire-related loads? In other words, would a non fire-rated transfer switch be required to feed the distribution panel? (If the answer is that another ATS is required, the 695.6(E) provision would seem analogous to NEC 700.5 that requires that an Article 700 Emergency ATS to supply only emergency loads and requires a separate ATS for optional standby or legally required loads.)
(4 ) Should a NFPA 110 generator be specified in fire pump applications? (I'm leaning yes per NEC commentary under 695.3(A) which states "performance requirements for the alternate source of electric power can be found in NFPA 110, Standard for Emergency and Standby Power Systems" and NEC commentary under 700.1 "Emergency systems are designed and installed to . . . provide power for . . . fire pumps")
Thanks in advance for the responses.
Context
An industrial facility desires to connect a generator to an existing fire pump application. Currently, a single 150 hp fire pump motor and 1.5 hp jockey pump controller is installed and located within a stand-alone pump house that is remote from the main plant. A walk down has revealed the electrical supply originates within switchgear located in an electrical room inside the plant and is supplied from an unmarked 600A low-voltage breaker located in a vertical section of switchgear with other breakers feeding industrial loads. The circuit routes leaves the room and routes underground to the stand-alone pump house and directly feeds an 800A distribution panel. The fire pump controller is then fed from a thermal-magnetic breaker located within the distribution panel. The distribution panel also feeds jockey pump and non-fire protection related loads (e.g., site lighting circuits).
Code Applicability
The local jurisdiction does not have an electrical inspector or fire marshal. However, a reasonable standard of care for electrical engineering design would seem to indicate that the NEC and NFPA 20 electrical requirements would nevertheless apply to the design and installation.
Does anyone have a differing view?
Are these legitimate code deficiencies in the existing configuration?
Reading 695 it seems (emphasis on seems) to indicate the existing configuration has code deficiencies listed below. Please note Code references are taken from NEC – 2020, Handbook.
(1) 695.3(A)(1), which requires a connection located ahead of (but not within) the service disconnecting means.
Reason: The connection is originates from a breaker within switchgear; it does originate ahead of the service disconnecting means.
(2) 695.4(B)(3)(a)(3), which prohibits a disconnecting means from being located within the same enclosure that supplies loads other than fire pump.
Reason: If the 600A breaker can legitimately function as disconnecting means, it cannot be located in the same switchgear section with breakers that supply industrial loads. This deficiency seems to apply both for the 600A breaker located in the switchgear inside the facility as well as the thermal-magnetic breaker located in the distribution panel in the pump house that feeds the fire controller.
(3) 695.4(B)(1)(a), which requires single disconnecting means and OCPD between the power source and the listed fire equipment.
Reason: Upstream of the listed fire controller, there are two disconnecting means installed: the 600A breaker and the thermal magnetic breaker in the local distribution cabinet.
(4) 695.4(B)(2)(a)(1), which requires overcurrent protection sized in accordance with locked rotor current of the fire pump.
Reason: The 600A breaker in the switchgear and thermal-magnetic breaker in the local distribution panel are not sized to tolerate the LRC of both the fire pump and jockey pump indefinitely. This conclusion is based on LRCs contained in T.430.251(b).
(5) 695.4(B)(3)(a), which requires the disconnect means to be suitable for use as service equipment and lockable in the closed position.
Reason: The breaker is currently not able to be locked in the closed position. This seems to apply to both breakers in the fire pump power circuit.
(6) 695.4(A), which requires the supply conductors to directly connect the power source to a listed fire pump controller, a listed combination fire pump controller and power transfer switch, or a listed fire pump power transfer switch.
Reason: The fire pump supply conductors do not directly terminate into a fire listed device, they terminate into a non-fire listed distribution panel within the pump house.
Remediation/ Generator Design Questions
By installing a generator it appears that the apparent code deficiencies above would need to be remediated along with a code compliant generator design.
(1) Am I correct in thinking the existing “normal supply” circuit would need to be re-configured such that “dedicated feeder [695.3(A)(3)]” is derived from a connection ahead of the service disconnecting means or derived from a direct connection to a transformer’s secondary terminals?
(2) Am I correct in thinking that the normal-supply “dedicated feeder” would need to have a direct connection to the fire pump controller such that when the circuit emerges into the pump house it only feeds the fire pump controller (and a jockey pump connection permitted if made in accordance with a Type 2 junction box [695.6(I)])?
(3) Does NEC 695.6(E) prohibit a listed fire ATS from feeding a distribution panel that would contain jockey pump as well as non fire-related loads? In other words, would a non fire-rated transfer switch be required to feed the distribution panel? (If the answer is that another ATS is required, the 695.6(E) provision would seem analogous to NEC 700.5 that requires that an Article 700 Emergency ATS to supply only emergency loads and requires a separate ATS for optional standby or legally required loads.)
(4 ) Should a NFPA 110 generator be specified in fire pump applications? (I'm leaning yes per NEC commentary under 695.3(A) which states "performance requirements for the alternate source of electric power can be found in NFPA 110, Standard for Emergency and Standby Power Systems" and NEC commentary under 700.1 "Emergency systems are designed and installed to . . . provide power for . . . fire pumps")
Thanks in advance for the responses.
