![]() If you connect through a disconnect and an overcurrent protective device (OCPD), then you can use a single disconnecting means and associated OCPD(s) between the fire pump power source and one of the following : If you have a direct connection, the supply conductors must directly connect the power source either to a listed fire pump controller or to a listed combination fire pump controller and power transfer switch. Ĭircuits that supply electric motor-driven fire pumps must be supervised from inadvertent disconnection whether the conductors connect directly or through a disconnecting means and overcurrent device. Phase converters are not permitted for a fire pump service. An approved combination of one of the sources in 695.3(A) and an on-site standby generator.Įxception to 695.3(B)(1) and (B)(2): An alternate source of power isn’t required where a back-up engine-driven or back-up steam turbine-driven fire pump is installed.Ī multi-building, campus-style installation where the sources just discussed aren’t practicable, follow the requirements of 695.3(C).Īn on-site standby generator as an alternate source, follow the requirements of 695.3(D).Īrrange multiple sources so that a fire at one source won’t cause an interruption at the other source. Individual source and on-site standby generator. An approved combination of two or more of the sources from 695.3(A). If reliable power can’t be obtained from one of these sources, then it must be supplied by one of the following multiple sources : Ī dedicated feeder derived from a service connection in accordance with 695.3(A)(1). Īn on-site power supply, such as a generator, located and protected to minimize damage by fire. Ī connection located ahead of (but not within) the service disconnecting means. It needs to be one or more of the following:Ī separate electric utility service. Įlectric motor-driven fire pumps must have a reliable source of power, which is subject to the approval of the AHJ. This source must be able to carry the locked-rotor current of the fire pump motor(s) and pressure maintenance pump motors, plus the full-load current of associated fire pump equipment. However, as with previous NEC editions, you must supply power from a reliable source. 695 have changed extensively (see SIDEBAR: Power Source(s) for Electric Motor-Driven Fire Pumps at end of article). With the 2011 NEC, the power requirements found in Art. The rules covering the installation of electric power sources and interconnecting circuits for switching and control equipment dedicated to fire pump drivers are very specific. It doesn’t cover the jockey pumps or the internal wiring of the system ( Photo). ![]() 695, it covers the installation of the fire pump supply and controls. For example, contrary to what other articles require, the disconnect must be lockable in the closed position. This doesn’t conflict with other requirements, but many Art. Obviously, the pump is more likely to keep running if its location minimizes exposure to fire, and doing so is an NEC requirement. Consequently, the many requirements of Art. If the pump doesn’t run, not only will those conductors be damaged, but the entire facility will also be in danger of burning down. 695 is based on a different philosophy: The fire pump motor must run, regardless of the risk to the conductors.Ī fire pump supplies water to a facility’s fire protection piping. The general philosophy behind most Code requirements is to provide circuit protection that will shut down equipment before the supply conductors become overloaded, overheated, and damaged. Note: This article is based on the 2011 NEC. If you’d like to see updated information on this topic, please check out this recently published article, Fire Pump Systems. Thank you for visiting one of our most popular classic articles. ![]()
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