2005 Nec Handbook (National Electrical Code, Nfpa 70)
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692.65
Article 695 — Fire Pumps
ARTICLE 695 Fire Pumps
interactive system is so designed that significant unbalanced voltages voltag es cannot result. (B) Thre Threee Phase Phase Three-phase interactive fuel cell systems shall have all phases automatically de-energized upon loss
Summary of Changes
of voltage, or upon unbalance of voltage in one or more phases, phas es, unl unless ess the int interac eractiv tivee syst system em is desi designe gned d so tha thatt significant signif icant unbalanced voltages will not result result..
692.65 Point of Connection Connection
• 695.2: Revised 695.2: Revised to make it clear that ‘‘fault tolerant’’ applies to the entire circuit, not just the conductors. 695.5(C)(2): Revised to spec• 695.4(B)(1), 695.5(B), and 695.5(C)(2): Revised ify tha thatt the requ require iremen mentt to carr carry y loc locked ked-rot -rotor or curr current entss indefinitely applies only to overcurrent devices in the fire pump motor supply circuit.
The ou The outp tput ut of a fue fuell cel celll sys syste tem m po powe werr sou sourc rcee sha shall ll be connected as specified in 692.65(A) or 692.65(B).
• 695.6(D): Revised to clarify that fire pump feeder and branch bra nch cir circui cuitt con conduct ductors ors are requ requiredto iredto have sho short-c rt-circ ircuit uit protection only.
(A) Supply Side A fuel cell system power source shall be permitted to be connected to the supply side of the service disconnecting means as permitted in 230.82(6).
695.6(E): Revised to permit listed Type MC cable with • 695.6(E): Revised an imp impervi ervious ous cov coveri ering ng as a fir firee pum pump p mot motor or wir wiring ing method on the load side of the controller.
(B) Loa Load d Sid Sidee A fuel cell system power source shall be permitted to be connected to the load side of the service disconnecting means of the other source(s) at any distribution tio n equi equipmen pmentt on the premises, premises, provided provided tha thatt all of the following conditions are met:
• 695.6(H): Added 695.6(H): Added new section prohibits ground-fault protection of equipment for fire pump supply circuits. • 695.14(E): Revised 695.14(E): Revised to permit listed Type MC cable with an impervious covering as a wiring method for fire pump control wiring.
(1) Each Each sour source ce int interco erconnec nnectio tion n shal shalll be mad madee at a ded dedica icated ted circuit breaker or fusible disconnecting means. (2) The sum of the ampere ampere ratings ratings of overcurren overcurrentt devices devices in circuits supplying power to a busbar or conductor shall not exceed the rating of the busbar or conductor. Exception: For a dwelling unit, the sum of the ampere rat Exception: ings of the overcurrent devices shall not exceed 120 percent of the rating of the busbar or conductor.
Contents 695.1 (A) (B) 695.2 695.3
Scope Covered Not Covered Definitions Defini tions Power Source(s) for Electric Motor-Driven Motor-Driven Fire Pumps (A) Individual Sources (B) Multiple Sources 695.4 Contin Continuity uity of Power
(3) The interco interconnec nnectio tion n poi point nt shall be on the lin linee sid sidee of all ground-fault protection equipment. (4) Equipm Equipment ent containing containing overcurrent devices in circuits suppl su pplyi ying ng po powe werr to a bu busb sbar ar or con condu duct ctor or sha shall ll be marked to indicate the presence of all sources. (5) Equipm Equipment ent such as circuit circuit breakers, if if backfed, shall shall be identified for such operation. (6) The circuit breaker breaker on the dedicated output output of a utilityinterac int eractiv tivee inv invert erter er sha shall ll be posi positio tioned ned in the dist distrib ributi ution on equipment at the opposite (load) end from the input feeder connection or main circuit location. A permanent warning label shall be applied to the distribution equipment with the following, or equivalent: WARNING FUEL CELL POWER SYSTEM OUTPUT. DO NOT RELOCATE THIS CIRCUIT BREAKER.
VIII. Outp Outputs uts Over 600 Volts 692.80 General Fuel cell systems with a maximum output voltage over 600 volts ac shall comply with the requirements of other articles applicable applic able to such instal installatio lations. ns. 1040 Copyright National Fire Protection Association Provided by IHS under license with NFPA
(A) Direct Connection (B) Supervised Connection 695.5 Tran Transformers sformers (A) Size (B) Overcurrent Protection (C) Feeder Source 695.6 Power Wiring Wiring (A) Service Conductors (B) Circui Circuitt Conduct Conductors ors (C) Conductor Size (D) Overload Protection (E) Pump Wiring (F) Junction Points (G) Mechanical Protection (H) Ground Fault Protection of Equipment
2005
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695.2
Article 695 — Fire Pumps
695.7 Voltage Drop 695.10 Listed Equipment Equipment 695.12 Equipm Equipment ent Location (A) Controllers and Transfer Switches (B) Engine Engine-Drive -Drive Controllers Controllers (C) Storage Batteries (D) Energized Equipment (E) Protection Against Pump Water (F) Mounting 695.14 Control Wiring Wiring (A) Control Circuit Failures (B) Sensor Functioning (C) Remote Device(s) (D) Engine-Drive Control Wiring (E) Electric Fire Pump Control Wiring Methods (F) Generator Control Wiring Methods FPN: Rule Ruless that are followed by a refere reference nce in brackets contain text that has been extracted from NFPA 20-2003, Standard Stand ard for the Installation Installation of Stat Stationar ionaryy Pumps for Fire Protection. Only editorial changes were made to the extracted text to make it consistent with this Code.
695.1 695 .1 Sco Scope pe (A) Cover Covered ed This This art articl iclee cove covers rs the ins instal tallat lation ion of the following:
and NFPA 20. Performance issues, including the determination of power supply reliability, are under the jurisdiction of the NFPA Technical Committee on Fire Pumps, while electrical installation requirements are within the purview of the National National Ele Electr ctrica icall Cod Codee Com Commit mittee tee.. Man Many y of the requirements in Article 695 are extracted from the 2003 edition of NFPA 20, as indicated by a bracketed reference at the end of the NEC requirement. requirement. Proposals for changes to the extracte extracted d requ require iremen ments ts in Article Article 695 have to be processed by the NFPA 20 committee because they have the primary responsi responsibili bility ty for that techni technical cal content. The scope of Articl Articlee 695, stated in 695.1, speaks to this division of responsibility. Article 695 does not apply to pumps used to supply sprinkler sprinkl er system systemss in one- and two-fam two-family ily dwellings. NFPA NFPA 13D, Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes, Homes , does not require the use of a listed pump; thus, neither NFPA 20 nor Article 695 is applicable. Although jockey pumps are not cov covered ered by Art Articl iclee 695, the they y are perm permitt itted ed to be connected to the fire pump feeder. Therequiremen Therequir ementsof tsof Art Articl iclee 695are ind indepen ependen dentt ofthose in Article 700 unless otherwise mandated by the authority having jurisdiction. Installation of the supply wiring to an electri ele ctricc mot motoror-dri driven ven fire fire pum pump p such as the one one sho shown wn in Exhibit 695.1 is covered by the requirements of Article 695.
(1) Electric Electric power sources and interconnecting interconnecting circuits circuits (2) Switch Switching ing and contro controll equipm equipment ent dedicat dedicated ed to fire pump drivers (B) Not Cover Covered ed This article does not cover the following: (1) The performance, performance, maintenance, maintenance, and acceptance testing testing of the fire pump system, and the internal wiring of the components of the system (2) Pressure maintenanc maintenancee (jockey or makeup) pumps FPN: See NFPA NFPA 20-2003, Standard for the Installation of Stati Stationary onary Pumps for Fir Firee Pro Protecti tection, on, for furth further er information.
Since it was first included in the 1996 NEC, Article 695 has been the subject of a number of important revisions, particularly in the requirements covering reliable power supplies for electric fire pump motors motors.. Many of those revisions correlate the requirements in the NEC NEC with with those in NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection. Protection. One of the most significant changes that has occurred in the evoluti evolution on of Article Article 695 is the the require requirement ment of of 695.3(B)(2) covering reliable power for electric fire pumps installed in multibuilding campus-style arrangements such as those found in many institutional institutional and indust industrial rial settings. It should be noted that there is a distinct division of responsibilit responsi bility y for fire pump requirements requirements between the the NEC NEC
National Electrical Code Handbook Copyright National Fire Protection Association Provided by IHS under license with NFPA
2005
Exhibit 695.1 An electric motor specifically listed for fire pump service. (Courtesy of International Association of Electrical Inspectors)
695.2 Defini Definitions tions Fault Tolerant External Control Circuits. Those control circuits either entering or leaving the fire pump controller enclosure, enclosu re, which if broken, disconnected, disconnected, or shorted will not prevent the controller from starting the fire pump from Document provided by IHS Licensee=ExxonMobil/1890500101, Licensee=ExxonMobil/1890500101, 05/05/2005 18:15:21 MDT Questions or comments about this message: please call the Document Policy Group at 303-397-2295.
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695.3
Article 695 — Fire Pumps
all oth other er int interna ernall or ext externa ernall mea means ns and may caus causee the controller to start the pump under these conditions. On-Site Power Production Facility. The Facility. The normal supply of electric power for the site that is expected to be constantly producing power. On-Site Standby Generator. A facility producing electric power on site as the alternate supply of electric power. It differs from an on-site power production facility, in that it is not constantly producing power.
695.3 Power Source(s) Source(s) for Electric MotorDriven Fire Pumps
enclosure, enclosu re, or vert vertica icall swi switch tchboa board rd sect section ion as the service service disconnecting means. The connection shall be located and arranged so as to minimize minimize the possib possibility ility of damage by fire from within the premises and from exposing hazards. A tap ahead of the service disconnecting means shall comply with 230.82 230 .82(5). (5). The serv service ice equ equipm ipment ent shal shalll com comply ply wit with h the labeling labeli ng requirements requirements in 230.2 and the location location requirements requirements in 230.72(B). [NFPA 20:9.2.2] (2) On-Site Power Production Facility A fire pump shall be permitted to be supplied by an on-site power production facility. The source facility shall be located and protected to minimize the possibility of damage by fire. [NFPA 20:9.2.3]
Electric motor-driven fire pumps shall have a reliable source of power.
Examples of power sources are illust Examples illustrated rated in Exhibi Exhibits ts 695.2 and 695.3. The power source for an electric motor-driven fire pump The determination of whether the serving electric utility must be reliable and have adequate capacity to carry the is a reli reliabl ablee source source of of power power is an issue issue for for the the autho authorit rity y locked-rotor currents of the fire pump motor and accessory having hav ing jur jurisdi isdicti ction. on. Ann Annex ex A of NFP NFPA A 20, 20, Standard Standard for equipment. equipm ent. These two main require requirements ments ensure that the the Instal Installati lation on of Stati Stationa onary ry Pumps Pumps for for Fire Fire Protec Protection tion,, fire pump will operate in the event of a fire without being provides guidance for evaluating the reliability of the power accidentally disconnected and that the fire pump will con supply. tinue to operate until the fire is extinguished, the fire pump Performance Performa nce require requirements ments for an altern alternative ative source of is purposely shut down, or the pump itself is destroyed. electr ele ctric ic pow power er can be foun found d in NFP NFPA A 11 110, 0, Standard Standard for One or more of the following three basic types of power Emergency Emer gency and Standby Power Systems Systems.. sources are permitted. permitted. If only one source is used, that source Most import important ant in 695.3(A 695.3(A)(2) )(2) is the requirem requirement ent that must be capable of supplying locked-rotor current to the fire a fire fire in one one source source of of power power not not affect affect the reli reliabi abilit lity y of pump and accessory equipment. Power may be supplied by anotherr source. anothe source. For exampl example, e, if an emerg emergency ency feeder were the following: physically physic ally routed above the normal switc switchboard hboard and a fire occurred in the normal switchboard, the reliability of the 1. A sepa separat ratee uti utilit lity y serv service ice or conn connect ection ion ahead of the emergency emerg ency feeder during the fire would be questi questionable onable.. main discon disconnectin necting g means There are many other examples for such interruption scenar2. An on-site on-site power production production system ios. The requirements for fire protection of the fire pump 3. Multi Multiple ple sources (two (two or more feeders) on a multibuildmultibuildsupply conductors are located in 695.6(A) and 695.6(B). ing campus where utility or power produced on site is not reasonably available available and this method of power supply is approved by the authority having jurisdiction (B) Multiple Sources Where reliable reliable power cannot be obIf none of these options is individually capable of pro tained from a source source describ described ed in in 695.3(A 695.3(A), ), power shall be viding reliable power with adequate capacity, a combination supplied suppli ed from an approved combin combination ation of two two or more of (two or more) of these sources or a combination of one or either of such sources sources,, or or from from an approved combin combination ation of more of the these se sour sources ces wit with h an onon-sit sitee sta standb ndby y gene generat rator or feeders consti constituti tuting ng two or more power sources as covered must be used. in 695.3( 695.3(B)(2), B)(2), or from an approve approved d combi combination nation of one or more of such power sources in combination with an on-site standby generator complying with 695.3(B)(1) and (B)(3). (A) Individual Sources Where reliabl reliable, e, and where capable of carrying indefinitely the sum of the locked-rotor current of the fir firee pum pump p mot motor(s or(s)) and the pre pressur ssuree mai mainte ntenanc nancee pump pum p mot motor(s or(s)) and the full full-lo -load ad curr current ent of of the asso associa ciated ted fir firee pump accessory equipment when connected to this power supply, the power source for an electric motor-driven fire pump shall be one or more of the following. (1) Electric Utility Utility Service Connection Connection A fire pump shall be perm permitt itted ed to to be sup suppli plied ed by by a sep separat aratee servi service, ce, or from from a connection located ahead of and not within the same cabinet,
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(1) Gene Generator rator Capacity Capacity An on-site generator(s) used to comply with this section shall be of sufficient capacity to allow normal starting and running of the motor(s) driving the fire pump(s) while supplying all other simultaneously operated load. Automatic shedding of one or more optional standby standb y loads in order to comply with this capaci capacity ty requirement shall be permitted. A tap ahead of the on-site generator discon dis connect necting ing mea means ns shal shalll not be requ require ired. d. The requ require irement mentss of 430.113 shall not apply. [NFPA 20:9.6.1]
2005
National Natio nal Electr Electrical ical Code Code Handboo Handbook k
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695.3
Article 695 — Fire Pumps
Fire pump service conductors tapped from building service conductors
Exhibit 695.2 Two permitted configurations configuration s for connecting to electric utility–owned service drops.
Utility-owned service drop Service conducto conductors rs Service point Separated from each other to minimize damage from a fire in the main service
Building service equipment
Main
Fire pump controller
Utility-owned service drops
Service conductors
Service conductors Service points
Separate fire pump service
Separated from each other to minimize damage from a fire in the main service
Fire pump service
Building service equipment
Main
Fire pump controller
two or more feeder sources shall be permitted as one power source or as more than one power source where such feeders are connected to or derived from separate utility services. The connection(s), overcurrent protective device(s), and disconnecting means for such feeders shall meet the requirements of 695.4(B). [NFPA 20:9.2.5.3]
Where the alt Where alterna ernativ tivee sour source ce of pow power er is an on-s on-site ite gene generat rator or,, the alternative alternative source discon disconnectin necting g means and the alternati na tive ve sou source rce ov overc ercur urren rentt pro prote tect ctiv ivee de devi vice ce(s) (s) fo forr th thee electr ele ctricic-dri drive ve fir firee pum pump p are not requ required ired to be siz sized ed for locked-rotor current of the fire pump motor(s). Rather, the circuit components of the alternative source are permitted to be sized according to Article 430, provided they ‘‘allow instantaneous pickup of the full [fire] pump room load,’’ as specified by 9.6.5 in NFPA 20. See 445.12(A).
The requirements of 695.3(B)(2) were an important revision to the 1999 Code Code,, permitting the use of feeder sources for campus-style applications. Chapter 9 of NFPA 20, Standard 20, Standard for the Installati Installation on of Stationa Stationary ry Pumps for Fire Protection Protection,, permits the use of a reliable feeder to supply a fire pump if it is acce accepta ptable ble to the aut authori hority ty havi having ng jur jurisd isdict iction ion.. See Exhibit 695.4. In NFPA 20, the use of a reliable feeder as
(2) Feed Feeder er Sources This section applies to multibuilding campus-style complexes with fire pumps at one or more buildings. Where sources in 695.3(A) are not practicable, and with the approval of the authority having jurisdiction,
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695.3
Article 695 — Fire Pumps
On-site power production facility located where it is protected from fire, such as outdoors or in a room of fire-rated construction
Exhibit 695.3 On-site power production facility as a power source for a fire pump installation.
Generator
Fire pump controller
Fire pump supply conductors
Exhibit 695.4 Multiple feeder sources for campus-style application, as described in 695.3(B)(2).
13.8-kV utility service No. 1
13.8-kV utility service No. 2
Multibuilding campus-style complex
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13.8 kV to 480Y/277 volt
13.8 kV to 480Y/277 volt Feeder 1
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To fire pump controller
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National Natio nal Electr Electrical ical Code Code Handboo Handbook k
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695.4
Article 695 — Fire Pumps
only. All disconnecting devices and overcurrent protective devices that are unique to the fire pump loads shall comply with 695.4(B)(1) through (B)(5).
a power supply for a fire pump is based on performance criteria, such as the following: 1. Redunda Redundant nt power supply supply features 2. Special requiremen requirements ts for generators
3. Special requiremen requirements ts for transfer switches switches 4. Generat Generator or overcurrent overcurrent protection protection
(1) Overcurr Overcurrent ent Device Selection The overcurrent protec
tive device device(s) (s) shall be select selected ed or set to carry indefi indefinitel nitely y the sum of the locked-rotor current of the fire pump motor(s) and the pressure maintenance pump motor(s) and the fullload loa d curr current ent of the ass associ ociate ated d fire pum pump p acc accesso essory ry equi equipmen pmentt when connected to this power supply. 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 circui circuit(s). t(s).
(3) Arra Arrangeme ngement nt The power sources shall be arranged so that a fire at one source will not cause an interruption at the other source. [NFPA 20:9.2.5.1]
695.4 Contin Continuity uity of Power
Circuits that supply electric motor-driven fire pumps shall be supervi supervised sed from inadver inadvertent tent disconnection disconnection as covered in 695.4(A) or 695.4(B).
(2) Disc Disconnec onnecting ting Means The disconnecting means shall comply with all of the following: (1) Be identified identified as suitable suitable for use as service equipment equipment (2) Be lockabl lockablee in the closed position position (3) Not be located within within equipment equipment that feeds loads other other than the fire pump
(A) Dir Direct ect Conne Connection ction The sup supply ply cond conduct uctors ors shal shalll directly connect the power source to either a listed fire pump controller contro ller or listed combination combination fire pump controller and power transfer switch. [NFPA 20:9.3.2.2.2] (B) Supervised Connection A single single disconn disconnecting ecting means means
A revision in the 2005 Code 2005 Code prohibits prohibits the supervised disconnecting nect ing mea means ns from bei being ng ins instal talled led in dis distri tribut bution ion equ equipm ipment ent that supplies other than fire pump loads. This change provides clear direct direction ion on how compli compliance ance with 695.4(B 695.4(B)(2)(4) )(2)(4) can be achieved. ‘‘Sufficiently remote from other building or oth other er fir firee pump source dis disconn connect ecting ing mea means’ ns’’’ can no longer be interpreted as permitting a supervised fire pump disconnecting means to be located in a switchboard or panelboard that supplies other than fire pump loads.
and associated overcurrent protective device(s) shall be permitted to be installed between a remote power source and one of the following: (1) A listed fire fire pump controller controller The requirement for sizing the overcurrent protection in a supervi sup ervised sed fir firee pum pump p dis disconn connect ecting ing means to be abl ablee to carry locked-rotor current indefinitely is a key factor in the reliable power source equation. Due to the critical life safety and property protection function of a fire pump, opening of the circuit by an overcurrent device installed between the point of connection to the power source and the fire pump controller cannot be tolerated and has to perform as if there were a direct connection to the power source. A change in the 2005 Code 2005 Code clarifies clarifies that sizing for locked-rotor current applies only to overcurrent protective devices and does not
(4) Be located sufficientl sufficiently y remote from other building or othe ot herr fi fire re pu pump mp sou sourc rcee di disc sconn onnec ecti ting ng me means ans suc such h that inadvertent contemporaneous operation would be unlikely (3) Disc Disconnec onnectt Marki Marking ng The disconnecting disconnecting means shall be marked ‘‘Fire Pump Discon Disconnectin necting g Means. Means.’’ ’’ The lette letters rs
extend to conductors or other devices in the fire pump motor circuit. Similar revisions to clarify this point are made in 695.5(B) 695.5( B) and 695.5( 695.5(C)(2). C)(2). (2) A listed fire fire pump power transfer transfer switch switch (3) A listed listed combinat combination ion fire pum pump p cont control roller ler and power power transfer switch Forr sy Fo syst stem emss in inst stal alle led d un unde derr th thee pr prov ovis isio ions ns of 695.3(B)(2) only 695.3(B)(2) only,, such addit additional ional disconnecting disconnecting means and associated associa ted overcur overcurrent rent protec protective tive device(s) shall be permit permit-ted as required to comply with other provisions of this Code Code.. Overcurrent protective devices between an on-site standby generator and a fire pump controller shall be selected and sized according to 430.62 to provide short-circuit protection
National Electrical Code Handbook
2005
shall be at least 25 mm (1 in.) in height, and they shall be visible without opening enclosure doors or covers.
(4) Contr Controlle ollerr Marki Marking ng A pla placard card shal shalll be pla placed ced adj adjace acent nt to the fir firee pum pump p cont control roller ler,, stat stating ing the loc locati ation on of thi thiss disc discononnecting nect ing mea means ns and the loc locati ation on of the key (if the dis discon con-necting nectin g means is locked locked). ). (5) Super Supervisio vision n The disconnecting means shall be supervised in the closed position position by one of the following methods: Minimizing the locations where the power supply to the fire pump can be automatically or manually interrupted is the objective of 695.4. Ideally, the supply conductors from the power source are run directly to the listed fire pump control
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695.5
Article 695 — Fire Pumps
and/or tra and/or transfe nsferr equ equipm ipment ent,, wit withou houtt the nee need d for an addi additio tional nal service disconnecting disconnecting means and overcurr overcurrent ent protect protection. ion. However, this arrangement is not always possible; therefore, a single supervised disconnecting means is permitted, pro-
of 750 750 ampe amperes res is is also also perm permitt itted, ed, beca because use it, too too,, will will carr carry y the locked-rotor current indefinitely.
vided all theinstalled conditions in fire 695.4(B) met. Where install ed in the pump are circuit, circui t, the supervi supervised sed disconnecting means with overcurrent protection must meet the following conditions:
and circuit breakers are sized according to locked-rotor currents, the feeder conductors to the fire pump and associated equipment are required to have an ampacity not less than 125 percent of the full-load current (FLC) rating of the fire pump motor(s) and pressure maintenance pump motor(s), plus 100 percent of associated accessory equipment. Using the same motors as above, calculate the size of the feeder to the fire pump controller as follows, using 430.6(A)(1) and Table 430.250 for the full-load currents of the motors:
STEP 2. Determine the minimum ampacity for the fire pump feeder conductor. Even though the disconnect switch, fuse,
1. The overcurrent overcurrent device device is sized to carry the locked-ro locked-rotor tor currents of all the fire pump motors. 2. The fire pum pump p dis disconn connect ecting ing means is loc locate ated d awa away y from the other service disconnecting means. This disconnecting means is rated as service equipment and is lockable in the on position. 3. The equ equipm ipment ent con contai tainin ning g the the dis disconn connect ecting ing mea means ns supplies only the fire pump and associated loads. 4. The disconnect disconnect and controlle controllerr are marked and placarded placarded as describ described. ed. 5. The circuit circuit is supervised supervised in in the closed closed position position,, in accoraccordance with 695.4(B 695.4(B)(5). )(5).
STEP 1. 1. Det Determi ermine ne the min minimu imum m rat rating ingss of the dis disconconnecting means and the overcurrent protective device. According to the motor nameplates, the locked-rotor current (LRC) is 725 amperes for the 100-hp motor and 20 amperes for the 1 1 ⁄ 2-hp motor. If the locked-rotor amperes are not on the nameplates, the locked-rotor currents found in Table 430.251(B) must be used. Calculate the size by summing the locked-rotor currents of both motors and then going to the next larger standard-size overcurrent device, as follows: 100-hp, 3-phase LRC 11 ⁄ 2-hp, 3-phase LRC Total LRC
725 A 20 A 745 A
The next larger standard-size standard-size disconnect switch and overcurrent devi device ce is 800 amp amperes eres.. An adj adjust ustabl able-t e-trip rip cir circui cuitt bre breaker aker
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100-hp, 3-phase FLC
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124 A
1.25
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155.00 A
11 ⁄ 2-hp, 3-phase FLC 1.25
3.75 A
Total Tot al FLC
158.75 A
3A
Example
Solution
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Specifically,, the size of the overcurrent protective Specifically protective device is the sum of the locked-rotor currents of all the permitted motors plus the sum of any other fire pump auxiliary loads.
A fusible service disconnect switch supplies power to a 100hp, 460-volt, 3-phase fire pump and to a 11 ⁄ 2-hp, 460-vol 460-volt, t, 3-phase jockey pump. The fire pump feeder circuit will be installed in a raceway between the disconnecting means and fire pump control controller ler.. The raceway is consid considered ered outside the building per 230.6. Using the requirements of Article 695, determine the sizes of the disconnecting means and overcurrent protection device. Also determine the minimum ampacity of the feeder conductors.
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or
159 15 9A
Thus, the minimum ampacity for the feeder conductors is 159 amperes. Using the 75 C column from Table 310.16, a 2/0 copper con conduct ductor or is the minimum minimum siz sizee requ require ired, d, per 110.14(C)(1)(b). Supervision of the disconnecting means by a local (protected premis premises) es) fire alarm system system,, central central statio station, n, proprie proprie-tary tar y supervis supervising ing stati station, on, or remote remote superv supervisi ising ng statio station n requires a connection to the premises fire alarm system. The connection is generally made through the use of dry contacts in the fire pump control controller ler that are connecte connected d to to a fire alarm system initi initiating ating device circui circuit. t. This circui circuitt is is programm programmed ed to generate a supervisory signal at the fire alarm control unit on loss loss of volta voltage ge to to the the fire fire pump pump control controller ler.. A supervi supervisory sory signal indica indicates tes that the suppress suppression ion system is ‘‘off-no ‘off-normal. rmal.’’ ’’ Connection of this device must initiate a supervisory signal and may also initiate a trouble signal. For more information, see NFPA see NFPA 72, 72, National Fire Alarm Code. Code. (1) Central Central sta statio tion, n, prop proprie rietary tary,, or rem remote ote sta statio tion n sign signal al device (2) Local signaling signaling service service that causes the sounding sounding of an audible signal at a constantly attended point (3) Locking the the disconnecting disconnecting means means in the closed position position (4) Sealin Sealing g of disconn disconnectin ecting g means and approved weekly recorded inspections when the disconnecting means are located within fenced enclosures or in buildings under the control of the owner [NFPA 20:9.3.2.2.3]
695.5 Transform ransformers ers Where the service or system voltage is different from the utilization voltage of the fire pump motor, transformer(s)
2005
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695.5
Article 695 — Fire Pumps
protected protect ed by dis discon connect necting ing mea means ns and over overcurr current ent prot protect ective ive devices shall be permitted to be installed between the system supply sup ply and the fire pum pump p cont control roller ler in acco accordan rdance ce wit with h 695.5( 695 .5(A) A) and (B), or (C). Only tra transfo nsformer rmerss cov covered ered in 695.5( 695 .5(C) C) sha shall ll be perm permitt itted ed to supp supply ly loa loads ds not directly directly associated with the fire pump system. (A) Size Where a transformer supplies an electric motordriven fire pump, it shall be rated at a minimum of 125 percent of the sum of the fire pump motor(s) and pressure maintenance pump(s) motor loads, and 100 percent of the associated fire pump accessory equipment supplied by the transformer. (B) Overcurr Overcurrent ent Protection Protection The primary overcurrent protective device(s) shall be selected or set to carry indefinitely the sum of the locked-rotor current of the fire pump motor(s) and the pressure maintenance pump motor(s) and the fullload loa d curr current ent of the asso associa ciated ted fir firee pum pump p acce accessor ssory y equ equipm ipment ent when connected connected to this power supply. supply. Secondar Secondary y overcurrent protection shall not be permitted. 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 circui circuit(s). t(s). See Exhibit 695.5. Dedicated Dedicat ed transfo transformer rmer and overcurre overcurrent nt protec protection tion sizing can be broken down into three basic requirements. requirements. Generally Generally stated, they are as follows: 1. The transfor transformer mer must be sized to at least 125 percent percent of the sum of the loads. 2. The transformer transformer primary overcurrent overcurrent device device must be at least a specified minimum size. 3. The transformer transformer secondary must not contain contain any overcurrent devices whatsoever.
Primary overcurrent protection only
Dedicated transformer Secondary conductors, overcurrent protection NOT permitted
Solution
STEP 1. Determine the minimum standard-size transformer. According to 695.5(A), to determine the minimum current value to use in the 3-phase power calculation, add the fullload currents of the fire pump motor(s) and jockey pump motor(s), then increase the total to 125 percent. The result of thi thiss calc calcul ulat atio ion n prov provid ides es th thee mini minimu mum m kV kVA rati rating ng of a tra transfo nsformer rmer dedicated dedicated to a fir firee pum pump p ins instal tallat lation ion.. Any transfo tra nsforme rmerr with with a kVA ratin rating g equal equal to or or great greater er than than the the
National Electrical Code Handbook Copyright National Fire Protection Association Provided by IHS under license with NFPA
2005
,
Jockey pump tap conductors
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Listed fire pump controller
Tap not permitted within fire pump controller
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Jockey pump disconnect, overcurrent protection, and motor controller
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Fire pump
M
M
Jockey pump
Exhibit 695.5 The overcurrent device in the primary of a transformer supplying a fire pump installation. The device is required to be sized to carry the locked-rotor l ocked-rotor current motor(s) motor(s) and associated fire pump accessory equipment indefinitely.
value determined by this calculation is acceptable. First, add the full-load currents of the two motors, using the full-load current (FLC) values from Table 430.250, as follows:
100-hp, 3-phase FLC 11 ⁄ 2-hp, 3-phase FLC
124 A 3A
Total FLC
127 A
Now, increase the sum of the fire pump motor Now, motor and the jockey pump motor to 125 percent, as follows:
Example
A 4160/48 4160/480-volt 0-volt,, 3-phase, dedicated transformer supplies power pow er to a 100100-hp, hp, 460-volt, 460-volt, 3-phase, 3-phase, code let letter ter G fir firee 1 pumpan pu mpand d toa 1 ⁄ 2-hp -hp,, 460460-vol volt, t, 3-ph 3-phase, ase, code let letter ter H joc jockey key pump. Using the requirements of Article 695, determine the sizes of the dedicated transformer and its primary overcurrent protection.
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`
127 A
1.25
158.75 A
Then, size the transformer as follows: Transformer kVA
Transformer kVA
amperes 3 1000 480 158.75 3 1000 131.98 kVA volts
Thus, the minimum-size transformer permitted by 695.5(A) is 131.98 kVA. The next larger standard-size transformer available is 150 kVA, but any larger size is permitted. STEP 2. Calcul Calculate ate the minim minimum-siz um-sizee primar primary y overcurr overcurrent ent protection protect ion device permitted for this transformer. transformer. Accordi According ng to 695.5(B 695.5(B), ), the minim minimum um primar primary y overcurre overcurrent nt protect protection ion
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695.6
Article 695 — Fire Pumps
device must allow the transformer secondary to supply the locked-rotor current (LRC) to the fire pump and, in this case, the jockey pump. The locked-rotor current of each motor must be individually calculated if it is not available on the motor In this example, however, we Acare assuming thatnameplate. only the kVA code letters are available. cording cord ing to 430. 430.7(B 7(B)) and using the maximum maximum val values ues for the individual code letters per Table 430.7(B), calculate the maximum maximu m locked locked-rotor -rotor currents, as follo follows. ws. For the 100-hp motor, code letter G: LRC
LRC
motor hp
100 hp
max. code letter value
1000 motor voltage 3-phase factor
6.29
kVA 1000 hp 460 3
789.49A
1
For the the 1 ⁄ 2-hp mot motor or,, code letter letter H (usi (using ng the sam samee formula) formula):: LRC
11 ⁄ 2 h hp p
7.09
kVA
hp
1000 460
13.35 A
3
For the total LRC: 100-hp LRC 11 ⁄ 2-hp LRC
789.49 A 13.35 A
Total LRC
802.84 A
or
803 A
Now, cal Now, calcul culate ate the equi equival valent ent LRC on the pri primary mary sid sidee of the transfo tra nsforme rmer, r, base based d on the cal calcul culate ated d LRC of the seco secondar ndary y of the transformer, as follows: LRCprimary
secondary voltage LRCsecondary primary voltage 480 V 803 A 4160 V 92.65 A or 93A
This value of 93 amperes represents the secondary LRC reflected to the primary side of the transformer. Because this value is the absolute smallest overcurrent overcurrent protec protective tive device permitted, the next larger standard size, according to 240.6, is 100 amperes. Thus, the minimum standard-size standard-size overcurrent protective device is 100 amperes. Conclusion
The calculation calculation for a 4160/4 4160/480-volt 80-volt,, 3-phase transformer transformer supplying a 100-hp fire pump and a 11 ⁄ 2-hp jockey pump, both at 460 volts, 3 phase, can be summarized as follows: 1. The smallest smallest standard-size standard-size transformer transformer that is permitted permitted is 150 kVA.
1048
2. The smal smalles lestt sta standar ndard-si d-size ze ove overcur rcurrentprotec rentprotectiv tivee devi device ce permitt perm itted ed on the primary primary of the transforme transformerr is 100 amperes. 3. A sec secon ondar dary y ov overc ercurr urrent ent pro prote tect ctiv ivee dev devic icee is no nott permitted. (C) Feed Feeder er Source Where a feeder source is provided in accorda acco rdance nce wit with h 695. 695.3(B) 3(B)(2), (2), tra transfo nsformer rmerss sup supply plying ing the fir firee pump system shall be permitted to supply other loads. All other loads shall be calculated in accordance with Article 220, including demand factors as applicable. (1) Siz Sizee Transformers shall be rated at a minimum of 125 percent of the sum of the fire pump motor( motor(s) s) and pressure maintenance pump(s) motor loads, and 100 percent of the remaining load supplied by the transformer. (2) Over Overcurr current ent Prot Protecti ection on The The tr tran ansfo sform rmer er si size ze,, th thee feeder size, and the overcurrent protective device(s) shall be coordinated such that overcurrent protection is provided for the transformer in accordance with 450.3 and for the feeder in accordance with 215.3, and such that the overcurrent protective device(s) is selected or set to carry indefinitely the sum of the locked-rotor current of the fire pump motor(s), the pressure maintenance pump motor(s), the fullload current of the associa associated ted fire pump accesso accessory ry equipment, and 100 percent of the remain remaining ing loads suppli supplied ed by the transformer. 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).
695.6 Power Wiring Wiring Power circuits and wiring methods shall comply with the requirements in 695.6(A) through (H), and as permitted in 230.90 230 .90(A), (A), Exception Exception No. 4; 230 230.94 .94,, Exc Except eption ion No. 4; 230.95, Exception No. 2; 240.13; 230.208; 240.4(A); and 430.31. (A) Serv Service ice Conduc Conductors tors Supply Supply cond conduct uctors ors shal shalll be phy physisically routed outside a building(s) and shall be installed as service entrance conductors in accordance with Article 230. Where supply conductors cannot be physically routed outside buildings, they shall be permitted to be routed through buildings build ings where instal installed led in accordan accordance ce with 230.6( 230.6(1) 1) or 230.6(2). Where a fire pump is wired under the provisions of 695.3(B 695.3(B)(2), )(2), this requirem requirement ent shall apply to all supply conductors on the load side of the service disconnecting means that constitute the normal source of supply to that fire pump. Exception: Wher Exception: Wheree there are multiple sources sources of supply with means mea ns for auto automati maticc con connect nection ion fr from om one sou sourc rcee to the othe otherr, the requirement shall apply only to those conductors on the 2005
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695.6
Article 695 — Fire Pumps
load side of that point of aut automa omatic tic con connect nection ion between between sources. (B) Circuit Conductors Fire pump supply conductors on the load side of the final disconnecting means and overcurrent device(s) permitted by 695.4(B) shall be kept entirely independent of all other wiring. They shall supply only loads that are directly associated with the fire pump system, and they shall be protected to resist potential damage by fire, structural failure, or operational accident. They shall be permitted to be routed through a building(s) using one of the following methods: The cir circui cuitt con conduct ductors ors cove covered red by 695. 695.6(B) 6(B) are tho those se tha thatt are installed instal led from the load side of the supervised disconnecting disconnecting means permitted by 695.4(B) to the fire pump controller or combination controller/transfer switch. Unlike service conductors, these supply conductors are installed on the load side of a short-c short-circuit ircuit protective protective device and are not required to be ins instal talled led on the outside outside of a bui buildi lding ng or str struct ucture. ure. However, if these supply conductors are run through a building fromthe dis discon connect nectingmeans ingmeans to the fire pum pump p equ equipm ipment ent room, they are required to be protected against the effects of a fire to ensure that power to the fire pump is not compromised. Encasement Encasem ent in 2 in. of concret concrete, e, as recogni recognized zed in 230.6 for service conductors, is one method permitted to isolate and protect conductors. In addition, enclosure of a wiring method within 1-hour fire-res fire-resistiv istivee buildi building ng constru construction ction and the use of a wiring method listed as an electrical circuit protective system with a minimum 1-hour fire rating are methodss permit method permitted ted for these circuit conductors conductors that do have short-circuit protection. These latter two wiring methods are recognized for protecting conductors against the effects of fire, but they are not recognized recognized as means by which conductors can be considered as being outside a building or other structure. Therefore, if the installation involves service conductors that have to be run through a building, the only available options, short of instal available installing ling a supervi supervised sed disconnectin nec ting g mea means, ns, are to ins instal talll the con conduct ductors ors ben beneat eath h not les lesss than 2 in. of concrete or to encase the conductors in 2 in. of concrete. It is important to understand the difference between a 1-hour 1-ho ur fire fire ratin rating g of an elec electri trical cal circ circuit uit,, such such as a cond conduit uit with wires, and a 1-hour fire-resistance rating of a structural member mem ber,, such as a wal wall. l. Simply Simply sta stated ted,, at the end of a 1-hour fire test on an electric electrical al conduit conduit with wires, the circui circuitt must mu st fun funct ctio ion n elect electri rical cally ly (no sh short ort ci circu rcuit its, s, gro ground unds, s, or opens are permitted). The circuit and its insulation must be intact int act and electri electrical cally ly function functioning ing.. A wal walll subjecte subjected d to a 1-hour 1-ho ur fire fire-res -resist istanc ancee tes testt mus mustt onl only y prev prevent ent a fir firee from passing pass ing throug through h or past the the wall, wall, without without regar regard d to damage damage to the wall. All fire ratings and fire-resistance ratings are
National Electrical Code Handbook
2005
based on the assumption that the structural supports for the assembly assembl y are not impair impaired ed by the effect effectss of the fire. Thee UL 20 Th 2004 04 Fire Resistan Volume 2, Resistance ce Dire Directory ctory,, Volume describes three categories of products that can be used in the fire protection of electrical circuits for fire pumps: various electrical circuit protective systems (FHIT), electrical circuit prote pro tect ctiv ivee ma mate teri rial alss (FH (FHIY IY), ), and fi fire re res resis isti tive ve ca cabl bles es (FHJR). (FHJ R). (The (The four four-le -lette tterr codes codes in parent parenthese hesess are the the UL product category guide designa designations. tions.)) For inform information ation on electrical electri cal circuit protect protective ive system systems, s, see UL Subjec Subjectt 1724, 1724, Fire Tests for Electrical Circuit Protective Systems. Systems .
(1) Be encased encased in a min minimu imum m 50 mm (2 in.) of concrete concrete (2) Be within an enclosed enclosed construction construction dedicated dedicated to the fire pump circuit(s) and having a minimum of a 1-hour fire resistive rating (3) Be a lis listed ted electric electrical al cir circui cuitt prot protect ective ive system system wit with h a minimum 1-hour fire rating
Exception: The supply conduct Exception: conductors ors located in the electrica electricall equipmentt room equipmen room wher wheree they they originate originate and in the the fire fire pump
room shall room shall not not be requ requir ired ed to have have the the mi minim nimum um 1-hour 1-hour fire separatio separation n or or fire fire resi resistance stance rating, unless otherwise otherwise required requ ired by 700.9(D 700.9(D)) of this Code. (C) Conduc Conductor tor Size
(1) Fir Firee Pum Pump p Mot Motorsand orsand Oth Other er Equ Equipm ipment ent Conductors supplyi supp lying ng a fire pump pump motor(s motor(s), ), pressur pressuree mainten maintenanc ancee pumps, and associa associated ted fire pump accessor accessory y equipm equipment ent shall have a ratin rating g not les lesss than than 125 125 perce percent nt of of the sum of of the the fire pump motor(s motor(s)) and pressure maint maintenance enance motor(s motor(s)) fullload current( current(s), s), and 100 percent of the associa associated ted fire pump accessory equipment. (2) Fir Firee Pump Motors Only Conductors supplying only a fire pump motor shall have a minim minimum um ampacity in accordance with 430.22 and shall comply with the voltage drop requirements requirem ents in 695.7. Listed fir Listed firee pum pump p con control troller ler and pum pump p com combin binati ations ons are available in a wye-start, delta-run configuration. From the controller to the motor there are six circuit conductors, and when the motor is in the run mode, the conductor conductorss tha thatt supply supp ly each each wind winding ing are are conne connecte cted d in paral parallel lel.. Prior Prior to to the 2005 edition of the Code, Code, the general rule in 695.6(C)(2) for siz sizing ing the cond conduct uctors ors supp supplyi lying ng a sin single gle fire pum pump p mot motor or required a minimum conductor ampacity not less than 125 percen per centt of th thee pu pump mp mo moto torr fu full ll lo load ad cur curren rentt rat ratin ing. g. A rev revis isio ion n to this requirement for the 2005 Code 2005 Code references references 430.22 for sizing sizi ng the con conduct ductors ors supp supplyi lying ng a sing single le mot motor or.. For For a wyewyestart, delta-run delta-run fire pump motor motor,, the minimum conductor ampaci amp acity ty for each of the six lea leads ds bet betwee ween n the the cont control roller ler and the motor is calculated as shown in the following example.
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695.7
Article 695 — Fire Pumps
Background Information
fer switch shall be installed in accor accordance dance with 695.6(B 695.6(B)) or protected in accor protected accordance dance with 430.52. The protection provided shall be in accordance with the short-circuit short-cir cuit current rating of the combination fire pump transfer switch controller or separate separately ly mounted transfer switch.
• Fire pump motor nameplate nameplate information: information: 30 hp, 3-phase 3-phase,, 460 volt • Tab able le 43 430. 0.25 250 0 ful fulll lo load ad cu curre rrent nt fo forr 50 hp mo moto tor: r: 65 • amperes Section 430.22(A) specifies motor circuit conductor minimum ampacity based on 125 percent of motor full load current • Sectio Section n 430.22(C) specifies specifies full load current for conductors on the load side of controller based on 58 percent of motor full load current
(E) Pump Wiring Wiring All wiring from the controllers to the pump motors shall be in rigid metal conduit, intermediate metal met al con condui duit, t, liq liquid uidtig tight ht fle flexib xible le met metal al cond conduit uit,, or liq liq-uidtight flexible nonmetallic conduit Type LFNC-B, listed Type MC cable with an impervious covering, or Type MI cable.
Calculation
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• 65 amperes amperes 0.58
1.25
,
47 amperes
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Minimum Conductor Size • Assuming Assuming 75C terminations in the controller and conductor insulation type THWN, ampacity selection from Table 310.16 8 AWG copper circuit conductors (50 amperes)
(F) Junct Junction ion Points Points Where wire connectors are used in the fire pump circuit, the connectors shall be listed. A fire pump
Analysis • There will be six 8 AWG copper conductors conductors between between the controller and the motor. • The com combin bined ed amp ampaci acity ty of the two cir circui cuitt con conduct ductors ors connected in parallel to each winding in the run mode is 10 100 0 am ampe peres res (co (comb mbin ined ed am ampac pacit ity y of tw two o 8 AWG conductors). • Comparison of controller load side circuit conductors with with minimum ampacity for circuit conductors from the power source to the line side of fire pump controller:
The requ require iremen mentt of 695 695.6( .6(E) E) doesnot app apply ly to lig light ht swi switch tches, es, convenience conveni ence recepta receptacles, cles, telephone outlet outlets, s, fire detect detectors, ors, and simil similar ar equipm equipment ent locate located d in in the fire pump room.
control controller ornot firebepump transfer transfe switch, switch, where provided, vid ed, ler shall sha ll usedpower as a jun juncti ction onrbox to supp supply ly oth other er equipm equ ipment ent,, includi including ng a pressure pressure maintena maintenance nce (jockey (jockey)) pump(s).. A fire pump(s) fire pump contro controller ller and fire pump power transfer switch, switch, where provide provided, d, shall not serve any load other than the fire pump for which it is intend intended. ed. (G) Mechanical Protection Protection All wiring from engine controllers troll ers and batter batteries ies shall be protect protected ed agains againstt physica physicall damage and shall be installed in accordance with the controller and engine manufacturer’s manufacturer’s instru instructions ctions..
65 amperes 1.25 81 amperes 4 AWG THWN copper circuit conductors
(H) Gro Ground und Fault Prot Protecti ection on of Equipm Equipment ent Ground fault protect prot ection ion of equ equipm ipment ent shall not be per permit mitted ted for fire pumps.
• The minimum minimum size for the conductors as determined determined here may have to be increased to comply with the mandatory voltagee drop performance require voltag requirements ments specifi specified ed in 695.7.
Ground-fault protection of equipment as specified in several (D) Overload Protecti Protection on Power circuits shall not have automatic tomat ic protect protection ion agains againstt overloa overloads. ds. BranchBranch-circuit circuit and feeder conductors shall be protect protected ed against short circuit only. Where a tap is made to supply a fire pump, the wiring shall be treated as service conductors in accordance with 230.6. The The appli applicable cable distance distance and size restrictio restrictions ns in 240.21 shall not apply. Exception No. 1: Conduct Exception Conductors ors between storage storage batteries and the eng engine ine sha shall ll not re requir quiree over overcurr current ent pr prote otectio ction n or disc discononnecting means. Exception No. 2: For on-site standby generator(s) rated to Exception produce prod uce continuou continuouss curre current nt in excess of 225 perc percent ent of the full-load amper amperes es of the fire pump motor motor,, the conducto conductors rs between the on-site generator(s) and the combination fire pump transfer switch contr controller oller or separatel separatelyy mounted mountedtranstrans1050 Copyright National Fire Protection Association Provided by IHS under license with NFPA
sections of the NEC NEC is not permitted to be used to protect compon com ponent entss of a fir firee pum pump p ins instal tallat lation ion.. (Th (Thee fun functi ction on of ground-fault groundfault protection protection of equipm equipment ent protec protection tion should not be confused confused with the the functi function on of GFCI protect protection ion for personpersonnel.) Although the protection afforded to equipment by this typee of gro typ groundund-faul faultt pro protec tectio tion n is a man mandat datory ory safe safety ty requ require ire-ment in certain circumstances, the need for an uninterrupted source of power power takes precedence precedence for fire pump installat installations. ions. See 230.95 230.95,, Except Exception ion No. 2, and 240.13 240.13(3). (3).
695.7 Voltage Drop
The voltag voltagee at the contro controller ller line termi terminals nals shall not drop moree tha mor than n 15 per percentbelow centbelow norm normal al (co (contr ntroll ollerer-rate rated d vol voltag tage) e) under motor starti starting ng condit conditions. ions. The volta voltage ge at at the the motor motor termin ter minals als shall not dro drop p mor moree tha than n 5 perc percent ent below the 2005
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695.14
Article 695 — Fire Pumps
(C) Stora Storage ge Batteries Batteries Storage batteries for fire pump engine gi ne drive drivess sh shal alll be su supp pport orted ed above above the floor floor,, secured secured against displacement, and located where they are not subject to physical damage, flooding with water, excessive temperature, or excessive vibration.
voltage rating of the motor when the motor is operating at 115 pe perce rcent nt of th thee fu full ll-l -load oad cur curren rentt rat ratin ing g of th thee mo moto torr. Exception: This limitatio Exception: limitation n shall not apply for emer emergency gency run mechanical starting. [NFPA 20:9.4]
695.10 Listed Equipment Equipment Diesel engine fire pump control controllers, lers, electric fire pump controllers, troll ers, electric motors, fire pump power transfer switches, switches, foam pump controllers, and limited service controllers shall be listed for fire pump service. [NFPA 20:9.5.1.1, 10.1.2.1, 12.1.3.1]
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(D) Energ Energized ized Equipment Equipment All energized equipment parts shalll be locat shal located ed at least least 300 mm mm (12 in.) in.) above above the floo floorr level. (E) Prot Protect ection ion Against Pump Water Fire pump controllers and power transfer transfer switches shall be locate located d or protected so that they are not damage damaged d by water escaping escaping from pumps or pump connections.
This requirement requirement parall parallels els those provisi provisions ons in NFP NFPA A 20, Standard for the Installation of Stationary Pumps for Fire Protection,, that require components used in fire pump sysProtection tems to be liste listed. d. The fire pump controller shown in Exhibit 695.6 is an example of the listed equipment covered under 695.10.
(F) Mount Mounting ing All fire pump control equipment shall be mounte mou nted d in a subs substan tantia tiall man manner ner on nonc noncomb ombust ustibl iblee supp support ort-ing structu structures. res. Neither NFPA 20, Standard 20, Standard for the Installation of Stationary Pumps for Fire Protection, Protection, nor this Code this Code mandates mandates a dedicated cat ed roo room m for the fir firee pum pump. p. How However ever,, NFP NFPA A 20 doe doess
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specify a suitable space for this equipment. Compliance with the 695.12(A) requirement that fire pump controllers controllers and transfe transferr switches be locate located d ‘‘ ‘‘as as close as practicable’’ to the fire pump motor that they control may require requ ire tha thatt addi additio tional nal spa space ce be avai availab lable le to achi achieve eve the minimum maintenance working space set forth in 110.26. Generally, fire pump controllers are housed in substantial enclosu enclosures res suitable suitable to protect the conten contents ts against against limited limited amounts of falling water and dirt. In addition, all energized parts in the enclosure must be mounted at least 12 in. above the floor. Typically, the floor space for this area is equipped with a floor drain. The require requirement ment of 695.12(F) 695.12(F) does not permit fire fire pump control cont rol equi equipme pment nt to be mou mounte nted d on com combust bustibl iblee bac backboa kboards rds (such as plywood). Exhibit 695.6 Listed fire pump controller and power transfer switch.
695.14 Contro Controll Wiring
Prior to bei Prior being ng shi shipped pped to the ins instal tallat lation ion site, lis listed ted fire pump controllers are matched with the listed electric motor(s mot or(s)) the they y wil willl con contro troll to ensu ensure re com compat patibi ibilit lity y of the individually listed components.
(A) Control Circuit Circuit Failures External control circuits that extend outside the fire pump room shall be arranged so that failure of any external circuit (open or short circuit) shall not prevent prevent the operatio operation n of a pump(s) from all other internal internal or extern external al means. Breakage, Breakage, disconnecting, disconnecting, shorting of the wires, or loss of power to these circuits could cause continuousrunnin ousrunn ing g of th thee fi fire re pum pump p bu butt sha shall ll no nott pre preve vent nt th thee co cont ntro rolller(s) from starting the fire pump(s) due to causes other than these external control circuits. All control conductors within the fire pump room that are not fault tolerant shall be protect te cted ed ag agai ains nstt ph physi ysical cal dam damag age. e. [N [NFP FPA A 20 20:1 :10. 0.5. 5.2. 2.6, 6, 12.5.2.5]
695.12 Equipme Equipment nt Location
(A) Contr Controlle ollers rs and Transf ransfer er Switc Switches hes Electric motor motor-driven fire pump control controllers lers and power transfer switches shall be located as close as practicable to, and within sight of, the motors that they control. (B) Engine Engine-Dri -Drive ve Contr Controlle ollers rs Eng Engine ine-dri -drive ve fire pum pump p controllers shall be located as close as is practical to, and within sight of, the engines that they control. National Electrical Code Handbook Copyright National Fire Protection Association Provided by IHS under license with NFPA
2005
(B) Senso Sensorr Funct Functioning ioning No undervoltage, phase-loss, frequency-sensitive, or other sensor(s) shall be installed that
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1051
695.14
Article 695 — Fire Pumps
automatically or manually prohibit actuation of the motor contactor. [NFPA 20:10.4.5.6]
The wiring methods described in 695.14(E) apply only to the cont control rol wir wiring ing for ele electr ctric ic mot motor– or–dri driven ven fir firee pum pumps. ps. The They y do not apply to the control wiring for engine-driven fire pumps, because there are no similar requirements in NFPA
Exception: A phase loss sensor(s Exception: sensor(s)) shall be permitted only as a part of a listed fire pump controller. (C) Remot Remotee Devic Device(s) e(s) No rem remote ote device(s) device(s) shall be installed that will prevent automatic operation of the transfer switch. [NFPA 20:10.8.1.3] (D) Engine-Drive Control Wiring All wiring between the controller and the diesel engine shall be stranded and sized to con contin tinuous uously ly car carry ry the cha chargi rging ng or cont control rol currents currents as required by the controller manufacturer. Such wiring shall be protected against physical damage. Controller manufacturer’ tur er’ss spec specifi ificat cation ionss for dis distan tance ce and wir wiree siz sizee shal shalll be followed. [NFPA 20:12.3.5.1] (E) Electric Electric Fir Firee Pump Contr Control ol Wir Wiring ing Meth Methods ods All electric motor-driven fire pump control wiring shall be in rigid metal conduit conduit,, interm intermediat ediatee metal conduit, liquidtight liquidtight flexible metal conduit, liquidtight flexible nonmetallic conduit Type B (LFNC-B), listed Type MC cable with an imper-
20, for Fire Standard Protection. Protection . the Installation of Stationary Pumps for
(F) Generator Control Control Wiring Methods Methods Control conductors instal installed led between the fire pump power transfer switch and the standby generat generator or supply supplying ing the fire pump during normal norm al power power loss loss shall shall be kept kept entir entirely ely inde independ pendent ent of of all other wiring wiring.. They They shall shall be protecte protected d to resist potent potential ial damage by fire or structural failure. They shall be permitted to be routed routed throug through h a build building(s) ing(s) encased in 50 50 mm mm (2 in.) of conc concret retee or wit within hin encl enclosed osed cons constru tructi ction on ded dedica icated ted to the fire pump circuits and having a minimum 1-hour fire resistance rating, or circuit protective systems with a minimum of 1-hour fire resistance. The installation shall comply with any restrictions provided in the listing of the electrical circuitt protec circui protective tive system used.
vious covering, or Type MI cable.
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1052 Copyright National Fire Protection Association Provided by IHS under license with NFPA
2005
National Natio nal Electr Electrical ical Code Code Handboo Handbook k
Document provided by IHS Licensee=ExxonMobil/1890500101, Licensee=ExxonMobil/1890500101, 05/05/2005 18:15:21 MDT Questions or comments about this message: please call the Document Policy Group at 303-397-2295.
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