(B) Connection Through Disconnecting Means and Overcurrent Device
- A listed fire pump controller
- A listed fire pump power transfer switch
- A listed combination fire pump controller and power transfer switch
(c) On-Site Standby Generator. Where an on-site standby generator is used to supply a fire pump, an additional disconnecting means and an associated overcurrent protective device(s) shall be permitted.
(a) Individual Sources. Overcurrent protection for individual sources shall comply with the following:
- Overcurrent protective device(s) shall be rated to carry indefinitely the sum of the locked-rotor current of the largest fire pump motor and the full-load current of all of the other pump motors and accessory equipment. [20:188.8.131.52] Where the locked-rotor current value does not correspond to a standard overcurrent device size, the next standard overcurrent device size shall be used in accordance with 240.6. The requirement to carry the locked-rotor currents indefinitely shall not apply to conductors or devices other than overcurrent devices in the fire pump motor circuit(s).
- Overcurrent protection shall be provided by an assembly listed for fire pump service and complying with the following:
- The overcurrent protective device shall not open within 2 minutes at 600 percent of the full-load current of the fire pump motor(s).
- The overcurrent protective device shall not open with a re-start transient of 24 times the full-load current of the fire pump motor(s).
- The overcurrent protective device shall not open within 10 minutes at 300 percent of the full-load current of the fire pump motor(s).
- The trip point for circuit breakers shall not be field adjustable. [20:184.108.40.206.1]
(b) On-Site Standby Generators. Overcurrent protective devices between an on-site standby generator and a fire pump controller shall be selected and sized to allow for instantaneous pickup of the full pump room load, but shall not be larger than the value selected to comply with 430.62 to provide short-circuit protection only. [20:220.127.116.11]
(a) Features and Location — Normal Power Source. The disconnecting means for the normal power source shall comply with all of the following: [20:18.104.22.168]
- Be identified as suitable for use as service equipment.
- Be lockable in the closed position. The provision for locking or adding a lock to the disconnecting means shall be installed on or at the switch or circuit breaker used as the disconnecting means and shall remain in place with or without the lock installed.
- Not be located within the same enclosure, panelboard, switchboard, switchgear, or motor control center, with or without common bus, that supplies loads other than the fire pump.
- Be located sufficiently remote from other building or other fire pump source disconnecting means such that inadvertent operation at the same time would be unlikely.
Exception to 695.4(B)(3)(a): For a multibuilding campus-style complex(s) installed under the provisions of 695.3(C), only the requirements in 695.4(B)(3)(a)(2) shall apply for normal power source disconnects.
(b) Features and Location — On-Site Standby Generator. The disconnecting means for an on-site standby generator(s) used as the alternate power source shall be installed in accordance with 700.10(B)(5) for emergency circuits and shall be lockable in the closed position. The provision for locking or adding a lock to the disconnecting means shall be installed on or at the switch or circuit breaker used as the disconnecting means and shall remain in place with or without the lock installed.
(c) Disconnect Marking. The disconnecting means shall be marked "Fire Pump Disconnecting Means." The letters shall be at least 25 mm (1 in.) in height, and they shall be visible without opening enclosure doors or covers. [20:22.214.171.124 (5)]
(d) Controller Marking. A placard shall be placed adjacent to the fire pump controller, stating the location of this disconnecting means and the location of the key (if the disconnecting means is locked). [20:126.96.36.199]
(e) Supervision. The disconnecting means shall be supervised in the closed position by one of the following methods:
- Central station, proprietary, or remote station signal device
- Local signaling service that causes the sounding of an audible signal at a constantly attended point
- Locking the disconnecting means in the closed position
(f) Sealing of disconnecting means and approved weekly recorded inspections when the disconnecting means are located within fenced enclosures or in buildings under the control of the owner [20:188.8.131.52]