nec elevator pit requirements
Other requirements: Spa's and Hot Tubs 1996 NEC 15-20 Amp 120 volt Receptacle Requirements for Dwelling units: All outdoor The locking capability is important so during maintenance, the equipment will not be inadvertently energized. These requirements, found in Article 620 (part of Chapter 6, Special Equipment), are in addition to NEC Chapters 1-3, which stipulate general wiring protocols applicable in most residential, commercial and industrial venues. He has focused on writing since 2006, having written for such magazines as ELEVATOR WORLD, Electrical Construction and Maintenance, Cabling Business, Electrical Business, Nuts and Volts, PV Magazine, Electrical Connection, Solar Connection, Solar Industry Magazine, Fine Homebuilding Magazine and Engineering News. Follow the manufacturers instructions and precautions. Home Articles Elevator World April 2012 Issue NEC Article 620: Elevators, Part I. A separate branch circuit shall supply the hoistway pit lighting and receptacle (s). On existing or listed equipment, conductors are permitted to be grouped together and taped or corded without being installed in a raceway. Pit light with guard (ten foot candles min. If the equipment must remain energized to perform work, effective insulation and safe electrical working practices should be observed. Article 620s Definitions section includes two terms that describe spaces not attached to the outside of a hoistway. A surge of immigration to the U.S., the end of slavery and, on both sides of the Atlantic Ocean, a burgeoning industrial revolution ignited an acceleration in new building. or larger, not exceeding 6 ft. in length, are permitted between control panels and machine motors, machine brakes, motor-generator sets, disconnecting means and pumping motors and valves. 0 A single dedicated receptacle supplying a permanently installed sump pump does not have to be a GFCI type. A little more narrowly focused (yet of great consequence) is the ubiquitous NEC, which, in the National Fire Protection Association (NFPA)s venerable Handbook edition, devotes 18 double-column pages to electrical design and installation requirements for elevators, escalators and related equipment. For all of this to come together in the real world, there had to be some assurance that these new technologies could be used safely on a wide scale. For elevators with battery lowering systems, an additional contact must be supplied and wired to disable the battery lowering system when the elevator disconnect is manually operated for maintenance. The demand factor ranges from 1.00 for one elevator on a single feeder to 0.72 for 10 or more elevators on a single feeder. hb``` ea``j~p2nfH 'xXg00,/(_ Iq8PDdg-~ s$!XI;Fn0vu `h`R 1y 0B.":9.@, e`xI;=7O3fvbb8:SC;%O*20] Section 725.45 concerns the location of overcurrent devices and provides for feeder and branch-circuit taps, transformer primary side overcurrent device location and overcurrent device location at the input side of electronic power sources. ranged from 0.06 cal/cm2 to 0.95 cal/cm2, which indicates that the arc-flash hazard to employees is primarily to the hands and arms. He had been with Eaton (Cutler-Hammer and Bussmann) since 1993 and specializes in training on the design and application of overcurrent protective devices and equipment in electrical distribution systems in accordance with the National Electrical Code and equipment in accordance with the various product standards. We resume with a look at wiring methods, overcurrent protection, grounding and other NEC provisions as they relate to these installations. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. 2.2.6.1 This switch shall be so located as to be acces-sible from the pit access door. 23.254.250.15 This position paper is written to provide guidance to members whose employees are engaged in elevator-industry work that might expose them to arc-flash hazards, and to assist members in complying with applicable OSHA and National Fire Protection Association (NFPA) standards. 974 0 obj <>/Filter/FlateDecode/ID[<64E135C225F1064D91BC8119D14516A9>]/Index[953 36]/Info 952 0 R/Length 105/Prev 204101/Root 954 0 R/Size 989/Type/XRef/W[1 3 1]>>stream Weight (passengers, freight, car and attendant machinery) may be fairly substantial, and speed is significant. The electrical energy does not traverse the human body, but proximity to the explosion means severe injury is possible from the intense heat and concussive shockwave. It is also essential that machine-room lighting be totally reliable and separate from the machinery supply to facilitate troubleshooting in the event of elevator problems. As such, elevator controller manufacturers should make the effort to rethink their designs to avoid costly system design changes. In many cases, the overcurrent protective devices that are suitable for this level of protection are current-limiting fuses rather than a traditional circuit breaker. They must be in enclosures with doors or removable panels that can be locked in the closed position. Sign up for our free e-newsletter. or larger, not over 6 ft. in length. Hydraulic elevator installations are typically supplied from the main switchboard and have an elevator fused switch or circuit breaker in the machine room that serves as the elevator disconnect. But the lights don't have to be in the pit itself. Cylinders in hydraulic elevators usually aren't suitable for buildings taller than five stories. All rights reserved. Furthermore, at least one 125-V, single-phase, 15- or 20-amp duplex receptacle is to be provided in each machine room or similar location. It is further stressed that no provision is to be made to open or close the disconnecting means from any other part of the premises. 953 0 obj <> endobj These are the principle NEC 2011 Article 620 mandates. It need not be exactly centered on the equipment, and working spaces of adjacent pieces of equipment may overlap. It is important to note, that these selective coordination tables can indicate a lack of selective coordination at a given fault current for circuit breakers that do not show overlap on the time-current curves of the circuit breakers. Motors for traction elevators were traditionally DC or synchronous, but new installations use AC motors and VFDs for speed control. As an installer and an inspector, one common issue I've seeen is incompatible connections associated with raceways connections and fittings. Part VIII, Machine Rooms, Control Rooms, Machinery Spaces, and Control Spaces, states elevator and similar-installation driving machines, motor-generator sets, motor controllers and disconnecting means are to be installed in a room or space set aside for that purpose. With the new elevator controller requirements, more attention will be focused on the elevator system. Here again, the lighting is not to be connected to a GFCI, whereas such protection is required for the receptacle(s). Where necessary, it is mandated that suitable guards be provided to protect the cables against damage. Many undertake trips in these devices two or more times daily in full confidence that they will survive an uneventful experience with a minute chance of disaster or even inconvenience. The thinking behind this requirement is that the injured worker could have severe hand burns and be unable to operate a conventional doorknob. Every building is different. If a smoke detector goes into alarm, it signals the elevator to go into Fire Recall Function, at which point the controller directs the elevator cab to travel to its pre-programmed designated landing, open its doors, and remain stopped there until the alarm clears. [emailprotected] For elevators that regenerate power back into a power source unable to absorb the regenerative power under overhauling elevator load conditions, a means to absorb this power is to be provided. The sump pump/drain shall have the capacity to remove a minimum of 11.4 m. 3 /h (3,000 gal/h) per elevator. Please check your entries and try again. Lights and convenience outlets in elevator pits shall be installed to comply with the requirements of CCR, Title 24, Part 3, Article 620. Finally, typical installations and compliance with all these requirements will be discussed. For example, it is stated that the cross-sectional area of the individual conductors in a wireway are not to exceed 50% of the interior cross-sectional area of the wireway. Limit switches placed throughout the height of the shaft communicate with the controller and stop the cab at each landing. After such an event, it is important that the affected worker is able to escape the area and get to help. (C) Duplex Receptacle. For this reason, the NEC provides for adequate working space around electrical equipment that may need to be serviced. An exception provides that liquid-tight flexible metal conduit or liquid-tight flexible nonmetallic conduit 3/8 in. Similar provisions are attached to elevator-car heating and air-conditioning disconnecting means, and to other utilization equipment. With the elevator car at the bottom landing, it is the length of cable as measured from the point of suspension in the hoistway to the bottom of the loop. The disconnecting means is to be an externally enclosed, operable, fused motor circuit switch or circuit breaker capable of being locked in the open position. Similarly, the integrity of the traveling cable is emphasized. You may go up to 600 V for power circuits supplying door-operator controllers and door motors, branch circuits and feeders to motor controllers, driving-machine motors, machine brakes and motor-generator sets. Beginning with Article 320, Armored Cable (Type AC) and concluding with Article 398, Open Wiring on Insulators, each code-sanctioned cable and raceway is treated, ranging from the familiar Type NM (trade name Romex) to the exotic Integrated Gas Spacer Cable (Type IGS). This may be countered by providing good machine-room ventilation. Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. Doors must open in the direction of travel and be equipped with panic bars, pressure plates or other devices that are normally latched but open under simple pressure. Moreover, it is necessary to consider future worker safety for an indefinite period. The 12 definitions provided in NEC 2011, Section 620.2 are the place to start for guidance in this area, and the sections that follow lay out implementation guidelines that are very relevant in todays environment. As mentioned, traditional installations of a traction or hydraulic elevator include a separate machine room. Dec. 21, 2010. A further requirement concerns elevator-car air-conditioning and heating. NEC 620.62 requires the elevator disconnecting means (fused switch or circuit breaker) to selectively coordinate with all supply-side overcurrent devices. This is because the material may contribute fuel to a fire that has originated elsewhere. The traveling cable or raceway is also permitted to include shielded conductors and/or one or more coaxial cables. Requirements in Article 620 modify the articles in Chapter 3. Use Underwriters Laboratories or Canadian Standards Association-labeled scopes tested for 1,000 V. Lockout/tagout: When troubleshooting is complete and further work can be accomplished without the equipment being energized, follow the lockout/tagout procedures in Section 7 of the. . Selective coordination is defined by the NEC as: Localization of an overcurrent condition to restrict outages to the circuit or equipment affected, accomplished by the selection and installation of overcurrent protective devices and their ratings or settings for the full range of available overcurrents, from overload to the maximum available fault current, and for the full range of overcurrent protective device opening times associated with those overcurrents.. Each of these performs a different function, and the wiring mandates vary accordingly. Cloudflare Ray ID: 7a2fbe9ebd7e2fe8 Reinforcing NEC 110.3(B) and NEC 110.10 to require the elevator controller marked SCCR to be equal to or greater than the calculated and The surest means of avoiding an arc-flash hazard is to lockout and tagout the electrical service to a controller. But, building codes had been in existence for many centuries. charlie b. It is worth noting that these NEC terms, used throughout Article 620, have been chosen to correlate with A17.1-2007 usage. For some manufacturers, such as Eaton, testing has been completed to determine the selective coordination ability of current-limiting BussmannTM series fuses with upstream Eaton circuit breakers. ), a duplex 15A 120-volt receptacle in pit with ground- fault circuit protection and a 15A 120-volt Non GFCI receptacle for the sump pump. And as the designer, you can become the fulcrum on which all of these requirements and authorities exert their leverage, but an understanding of elevator basics can help you handle the pressure. ,l7CLHmcX9*F -{Q|^"XL`b1y]$,y *R/2Rn{\xG L*vMP.uKW,)68]Y}+ FYS1B=Q0S>Hc A single means for disconnecting all ungrounded main power-supply conductors is required and must be designed so no pole can be operated independently. Hoistway pit lighting and receptacles 5. These selective coordination tables for current-limiting fuses show the minimum amp ratio required between a pair of fuses of a given type(s) to achieve selective coordination. All of these options and special wiring can be challenging depending upon the location of the shunt trip circuit breaker as well as who has responsibility for providing these additional options. Another important electrical system design consideration for supplying power to multiple elevators is NEC 620.62. The two main types of elevators are hydraulic and traction. ELECTRIC PASSENGER & FREIGHT ELEVATORS ASME A17.1 2004 Electric Elevator Checklist 2004 Multi-car.doc Page 4 of 44 Page Completed for cars : - Last Updated: 8/1/05 Car Enclosure Electric 2.14 - Hydraulic 3.14 A17.1 (A17.2) COMMENTS CARS 1-6 Operating Control Devices ADA Requirements This will normally require you to vent the room with a fire/smoke damper and include smoke detector signals in the control logic. A traction elevator's equipment room is typically located at the top of the building, directly over or adjacent to the shaft. And so the needs can be very different. Each fused switch or circuit breaker in the panelboard is used as an elevator disconnect. While machine room-less designs have been commercially available for many years, their use may still be unknown to some AHJs. Accordingly, the supply wires are protected only for short circuit, and the overload protection is provided closer to the motor. Hydraulic reservoir characteristic of a hydraulic-piston-operated elevator. Many professionals believe the NEC is applicable only for voltages over a certain level, but that is not the case. Many new buildings are incorporating an elevator design that does not include an equipment room (sometimes called machine room-less elevators). You'll need to run telephone cables to the equipment room control panel, but the elevator supplier will take care of getting the cables to the elevator cab. (B) Lighting Switch. Main feeders that supply elevator power must be kept outside the hoistway unless one of the following applies: Feeders for elevators are permitted within an existing hoistway (provided they are not spliced within the hoistway) by special permission of the AHJ. Additional requirements concern escape routes. Cross-sectional areas of wireways are found by multiplying the two interior dimensions.) It is further stipulated that internal voltages of power-conversion equipment and functionally associated equipment, and the operating voltages of wiring interconnecting the equipment, are permitted to be higher, provided that the equipment and wiring are listed for the higher voltages. All Rights Reserved | Contact Us | Privacy Policy. The disconnecting means is also to be a listed device. Per the 2017 NEC, if the elevator is designated as an emergency system load, the disconnect must be protected by a surge protective device (SPD). A section on branch circuits for car lighting, receptacles, ventilation, heating and air-conditioning contains a number of important provisions. Even though Edison grasped the basic ideas of fusing and overcurrent protection, many hazards remained. If the smoke detector at the designated landing goes into alarm, the elevator will stop at a predetermined alternate floor, which is usually the floor above the designated floor. Since 1953, Elevator World, Inc. has been the premier publisher for the global vertical transportation industry. This device must be either a fused disconnect or a circuit breaker because ANSI/ASME A17.1 requires you to install an additional overcurrent protection device (OCPD) in the elevator equipment room. All rights reserved. Thus, the need for door interlock functionality is recognized. It is further stated that the disconnecting means are not to disconnect the branch circuits required in sections 620.22, 620.23 and 620.24. Cables used in Class 2 power-limited circuits are permitted between risers and signal equipment and operating devices, provided they are supported and protected from physical damage and are of the jacketed and flame-retardant type. If power is not being supplied to the elevator controller (e.g., open mainline fuses, etc. This website is using a security service to protect itself from online attacks. Power for the elevator controller must first enter a lockable safety disconnect device, located adjacent to the door of the equipment room. In addition, requirements for selective coordination and shunt tripping should be complied with as needed for the installation. The light switch in the pit must be mounted 42 in. The two documents are in harmony and should be used in conjunction. (All intentionally grounded elements must be held at equal potential.) Metal grating shall be installed over the hole that sits flush with the pit floor. As for height, the working space must extend from the grade, floor or platform to 6-1/2 ft. or the height of the equipment, whichever is greater. If elevators are supplied by the emergency, legally required standby or critical operation power systems, then selective coordination is required per the 2017 NEC in 700.32, 701.27 or 708.54. It is stated that traveling cables are to be suspended at the car and hoistway ends, or counterweight end where applicable, so as to reduce the strain on the individual copper conductors to a minimum. If you can illuminate the pit using lights that are "above the top of the pit" (whatever that . He has focused on writing since 2006, having written for such magazines as ELEVATOR WORLD, Electrical Construction and Maintenance, Cabling Business, Electrical Business, Nuts and Volts, PV Magazine, Electrical Connection, Solar Connection, Solar Industry Magazine, Fine Homebuilding Magazine and Engineering News. No provision is to be made to automatically restore power. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. Specifically, Section 725.43 provides that overcurrent protection for conductors 14 AWG and larger is to be provided in accordance with the conductor ampacity without applying ampacity adjustment and correction factors. As always, the best advice in all instancesdo your homework, communicate often, and document decisions made. Flexible metal, liquid-tight flexible metal or liquid-tight flexible nonmetallic conduit 3/8 in. Requirements for commercial garages per the National Electrical Code. This requirement applies to all controllers, disconnecting means and other electrical equipment that may need servicing, inspection or maintenance. You are seeing this message for one of three reasons: You have reached your limit of free content. The many codes and guidelines that regulate the electrical design of an elevator can seem overwhelming, and dealing with the electrical inspector, elevator inspector, and Fire Marshal can be even more intimidating. endstream endobj startxref When you consider that an elevator is an enclosed room with one or more doors that people voluntarily enter so they may travel hundreds of feet up or down, several observations are in order. The various items to consider and check when designing for elevator installations have many potential pitfalls. Regardless of the number of elevators, only one smoke detector is required at each floor lobby, but it must be located within 21 ft of every elevator door. A separate 120VAC, 15A circuit is required for cab lighting and accessories, and it must have its own local disconnect and OCPD in the equipment room as well. This clear working space must be 30 in. This switch will ensure that the elevator won't descend into the elevator pit and allow maintenance people to work safely in the area beneath the cab. This is not the elevator companys responsibility. The Americans with Disabilities Act Accessibility Guidelines for Buildings and Facilities (ADAAG) now require the cab to have a special phone accessible by individuals with disabilities. Additional branch circuits are to supply other utilization equipment not covered above. Based on the analysis, the arc-flash boundaries at the elevator/escalator controllers ranged from 3-16 in. or larger is permitted to be installed in lengths in excess of 6 ft. Where motor-generators, machine motors or pumping-unit motors and valves are located adjacent to or underneath control equipment and provided with extra-length terminal leads not exceeding 6 ft. in length, such leads are permitted to be extended to connect directly to controller terminal studs without regard to carrying-capacity requirements. (g) Stop Switch in Pits. Besides the power-supply disconnect discussed, it is provided that elevators have a single means for disconnecting all ungrounded car lights, receptacles and ventilation power-supply conductors for that elevator car. Corporate Office NEC Article 620 covers elevators, dumbwaiters, escalators, moving walks, platform lifts and stairway chairlifts. Similarly, underground wiring in mines is not NEC regulated, although other, non-mine wiring below ground (such as lighting in an underground traffic tunnel) is covered. Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page. Traveling cables are to be approved for hazardous locations and must comply with the appropriate sections for each hazardous-location class that covers use of flexible cords. In an elevator machine room, where space may be limited in the first place, the working-space mandate must be factored in very early in the design process lest an unthinkable amount of rework be necessary. Part VII, Overcurrent Protection, divides this topic into four categories for elevators and similar equipment, depending upon the nature of the specific equipment: For operating devices and control and signaling circuits, protection against overcurrent is in accordance with the requirements of Sections 725.43 and 725.45. NEC has a further note that the term wheelchair lift has been changed to platform lift.. It begins by considering metal and nonmetallic wireways. Supports for cables or raceways in a hoistway or in an escalator or moving-walk wellway or platform lift and stairway chairlift runway must be securely fastened to the guide rail, escalator or moving-walk truss, or to the hoistway, wellway or runway construction. Selective coordination is also required for multiple elevators per NEC 620.62. Auxilliary gutters are permitted in machine and control rooms between controllers, starters and similar apparatuses. 68 | WWW.ELEVATORWORLD.COM | June 2012 Continuing Education . Your elevator supplier will take care of all the wiring and related code requirements for the elevator cab and the various controls. Part IX, Grounding, states that metal raceways, Type MC cable, Type MI cable or Type AC cable attached to elevator cars are to be bonded to metal parts of the car bonded to the equipment grounding conductor. It is also worth mentioning that the stated purpose of the NEC is the practical safeguarding of persons and property from hazards arising from the use of electricity. These must also be insulated for the maximum voltage applied to any conductor within the cable or raceway system. The electrical system designer needs to communicate this information to the person responsible for specifying the elevator controller, which is most often the architect. PK ! Hydraulic elevators are typically more cost effective and used for buildings up to 5-6 stories. Flexible cords and cables, or conductors grouped together and taped or corded, are permitted to be installed without a raceway. In order to comply, the electrical system designer must determine the maximum available fault current at the elevator disconnecting means and assure the elevator disconnecting means overcurrent protective device will clear any overcurrent condition, up to the maximum available fault current, before any upstream overcurrent devices will operate. Fuses: Verify that the correct size, type and capacity are installed. Car lighting, receptacles and ventilation 2. If the disconnecting means is an integral part of the motor controller, it is to be operable without requiring opening of the enclosure. Of particular importance is the location of the disconnecting means so it can be found by an individual who may not be familiar with the installation. employees shall not perform any work on equipment where there is a potential to come in contact with energized mechanical or electrical hazards until all sources of energy have been de-energized, grounded or guarded.. 2.2.2.6 . These are the individual branch circuits required for car lighting, receptacles, auxiliary lighting and ventilation on each elevator car; individual branch circuits for machine-room and similar location lighting and receptacle; and branch circuits for hoistway pit lighting and receptacle(s). IAEI News Magazine. Please check your entries and try again. : inspecting; troubleshooting; observing; etc.) Heating and air-conditioning equipment located on the car must not be in excess of 600 V. All live parts of electrical apparatuses are to be enclosed to protect workers and the public against accidental contact.