nec elevator pit requirements

You are seeing this message for one of three reasons: You have reached your limit of free content. 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. 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. 2. 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. 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. (e) Pit Maintenance. Article 620 follows this pattern by opening, in Section I, General, with a statement of scope and definitions applicable to the topic under consideration. You need to Subscribe to continuing reading. To avoid this situation, designers can specify elevator controls with a safety feature commonly called a rescuvator. 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. . Installing electrical equipment where its SCCR is less than the available short-circuit current creates serious safety hazards. The electrical conductors and equipment for non-mine elevators that extend below grade are under NEC jurisdiction. The pump sends hydraulic fluid from the reservoir to the cylinder, buried deep below the elevator shaft. C.1.4 ELEVATOR PIT REQUIREMENTS 1. Moreover, because motors have a higher starting current than other loads, the overcurrent protection protocol is unique to them and somewhat counterintuitive. !>x=yy Bvv8?~e PK ! Motor controllers are permitted outside the spaces specified above. This is typically accomplished via a shunt trip device. 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 836 Troy Schenectady Road ; Latham, NY 12110 . 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. Indeed, most elevator accidents involve maintenance workers, yet even theirs is not an excessively dangerous profession. Something went wrong. Please check your entries and try again. 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. Flexible cords and cables that are components of listed equipment and used in circuits operating at 30 V (42 VDC) or less are permitted in lengths not to exceed 6 ft., provided the cords and cables are supported and protected from physical damage and are of a jacketed and flame-retardant type. above the pit floor, shall: Be weatherproof (NEMA 4). 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. Fluid pressure in the cylinder raises and lowers the elevator cab. The design engineer must identify the available fault current at the elevator controller to the installer so an elevator controller with adequate SCCR can be provided. 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. 2.2.2.6 . The traveling cable, moreover, may be run without raceway from inside the hoistway to elevator-controller enclosures and to the elevator car and machine room and similar locations outside the hoistway for a distance not exceeding 6 ft. Requirements for commercial garages per the National Electrical Code. This is not the elevator companys responsibility. endstream endobj startxref Hydraulic reservoir characteristic of a hydraulic-piston-operated elevator. A traditional elevator installation (which includes a machine room) requires access inside the elevator shaft. The conduit alone can't act as the grounding means. 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. Guarding: Where possible, install temporary guarding to protect from inadvertent contact. PK ! We have circuited the receptacles and lights in the pits to the same circuit. 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). Bonding of elevator rails to a lightning-protection system grounding conductor is permitted, but the conductor itself is not to be located in the hoistway. +91 8025357028, 2022 Elevator World, LLC. Flexible metal, liquid-tight flexible metal or liquid-tight flexible nonmetallic conduit 3/8 in. Flexible cords and cables (same conditions as within hoistways). For example, an inadequately supported ceiling fan could fall and cause injury or property damage. You are a subscriber that needs to Sign In. U.S. Latham, NY Shopping Miscellaneous Retail Stores, NEC Wheelchair lifts EazyLift Elevators, . These circuit breaker selective coordination tables can be used to identify the maximum fault current that a pair of circuit breakers can selectively coordinate. Additional branch circuits are to supply other utilization equipment not covered above. 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. 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. Have wiring identified for use in wet locations in accordance with the requirements in NFPA 70. It is conditionally provided that fiber-optic cables and conductors for operating devices, operation and motion control, power, signaling, fire alarm, lighting, heating and air-conditioning circuits of 600 V or less are permitted to be run in the same traveling cable or raceway system. As stated in Section 7 of the Elevator Industry Field Employees Safety Handbook: Unless it is not feasible, (i.e. above the seal plate, adjacent to the ladder. Finally, in 1897, the first National Electrical Code (NEC) appeared. The fire loading resulting from an accumulation of abandoned low-voltage cabling may be considerable, and has to be understood and dealt with. 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. Many new buildings are incorporating an elevator design that does not include an equipment room (sometimes called machine room-less elevators). 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. Sign up for our free e-newsletter. As they review the plans and the construction site, they may have conflicting interpretations or requirements. Within cars, these additional wiring methods are permitted: The following additional wiring methods are permitted on the car assembly in lengths not exceeding 6 ft.: Within machine rooms, these additional wiring methods are permitted: The following wiring methods are permitted on the counterweight assembly in lengths not to exceed 6 ft.: Having looked at NEC 2011 mandates for elevator and related equipment installations, we will cover wiring methods, overcurrent protection, grounding and other related NEC provisions in part two of this series , running in the April 2012 issue of ELEVATOR WORLD. Traditionally, the electrical system design engineer has given little attention to the elevator controller. Home Articles Elevator World April 2012 Issue NEC Article 620: Elevators, Part I. All rights reserved. Flexible cords and cables, or conductors grouped together and taped or corded, are permitted to be installed without a raceway. This may be countered by providing good machine-room ventilation. This requirement applies to all controllers, disconnecting means and other electrical equipment that may need servicing, inspection or maintenance. It is noted that the article covers the installation of electrical equipment and wiring for elevators, dumbwaiters, escalators, moving walks, platform lifts and stairway chairlifts. As recommended in NFPA 70E, the National Elevator Industry, Inc. (NEII) commissioned an arc-flash hazard analysis (in compliance with IEEE Standard 1584-2002 for procedures for calculating the incident energy of the arc flash) by an independent consultant to determine at what level an arc-flash hazard exists to employees who work on energized elevator equipment. (f) Illumination of Pits. The main impetus for the creation of the NEC in the closing years of the 19th century was the collective anguish experienced by insurance underwriters who were losing vast amounts of money due to liability and physical damage claims resulting from Edisons electrification of, first, Lower Manhattan and then the world. Other requirements: Spa's and Hot Tubs 1996 NEC 15-20 Amp 120 volt Receptacle Requirements for Dwelling units: All outdoor In some cases, it may require a means to test the shunt trip operation or have one contact operate the shunt trip of more than one elevator. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. Mobile, AL 36606 USA 2m9 `K]f*F gaR The elevator rails, like the ground system of the entire building electrical structure, are to be bonded to the lightning-system ground electrode so these all remain at the same potential even during a lightning event, ensuring side flash does not occur. You are a subscriber that needs to Sign In. To address this issue, Code Making Panel (CMP) 12 of the National Electrical Code acted on several proposed changes to Article 620 during the revision cycle for the 2017 NEC that deal with the proper installation of elevator controllers. Requirements in Article 620 modify the articles in Chapter 3. The new ADAAG guidelines now require that emergency power be available to elevators that have four or more stories of travel above or below the accessible floor [4.1.3(9)(1)]. NFPA 72 requires the control circuit between the Fire Alarm System and the shunt trip be monitored for integrity. The circuit(s) for the lighting and receptacles must be dedicated to the elevator area only. (A) Separate Branch Circuit. Mainline disconnect: DO NOT OPEN THE MAINLINE DISCONNECT SWITCH COVER unless employees are authorized, properly trained and appropriate measures are taken commensurate with the higher risk of arc-flash hazards. 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 One. 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 Special conditions: Troubleshooting in wet, hot or cold conditions calls for extra caution. Finally, typical installations and compliance with all these requirements will be discussed. The locking capability is important so during maintenance, the equipment will not be inadvertently energized. The various items to consider and check when designing for elevator installations have many potential pitfalls. A further requirement concerns elevator-car air-conditioning and heating. Even though Edison grasped the basic ideas of fusing and overcurrent protection, many hazards remained. Traveling cables are to be supported by one of these means: Looping the cables around supports for unsupported lengths less than 100 ft. David Herres holds a New Hampshire Master Electricians license and has worked as an electrician in the northern part of that state for many years. Section 620.62, Selective Coordination, is central to multi-elevator installations and must be closely observed. This is something that can be easily accomplished if the elevator controller manufacturer uses components in combination with overcurrent protective devices that are tested and listed with high combination SCCRs. They are to be part of listed equipment, a driving machine or a driving-machine brake. In this case, it may be best if the elevator controller manufacturer does not include the elevator disconnecting means (often offered as a circuit breaker) but instead have the installer provide a separate fused disconnect to comply with NEC 620.51(A) and also achieve a high SCCR for the elevator controller when fuses are provided as specified by the elevator controller and marked on the elevator controller nameplate. Any other utilization equipment associated with the elevator Upon loss of power, the rescuvator controls the cab, lowers it to the designated floor, and opens its doors. This may be countered by providing good machine-room ventilation. Traction elevators are typically faster and more energy efficient than hydraulic elevators, and are often used for high-rise buildings. It is of great importance for the design engineer to communicate with their local authority having jurisdiction (AHJ) to determine fire alarm requirements for the respective elevator installation. This is because the material may contribute fuel to a fire that has originated elsewhere. From the website: Mohawk Lifts offers car lifts and auto lifts for purchase, including 2 post lifts, 4 post lifts, storage lifts, heavy duty mobile column lifts, parallelogram lifts, and other specialty items. We shall now take a look at the principle requirements of Article 620, with particular emphasis on wiring requirements for elevator shafts, machine rooms and cars. These conductors may be covered with suitable shielding for telephone, audio, video or higher-frequency communications circuits. In Part One of this series (ELEVATOR WORLD, April 2012), we began an examination of National Electrical Code (NEC) 2011 mandates for elevators and related equipment installations. GET YOUR CEUS TODAY, 1998-2021. hbbd```b``+3dL `Y[gw9`RLJO*A$w$@L`F*{|0 P It is of great importance that power to the various elevator functions can be quickly and reliably removed from the loads in case of emergency or for maintenance and troubleshooting. Conductors supplying a single motor are to have an ampacity not less than the percentage of motor nameplate current determined from Section 430.22(A) and (E). 3. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. A few years later, in 1880, Werner von Siemens built the first electric elevator, setting the stage for a new industry that would change the world by making the practical use of tall buildings possible. As such, elevator controller manufacturers should make the effort to rethink their designs to avoid costly system design changes. Where multiple driving machines are connected to a single elevator, there is to be one disconnecting means to disconnect the motor(s) and control-valve-operating magnets. They are permitted to be run without raceway when used inside the hoistway, on the elevator car, hoistway wall, counterweight, or controllers and machinery located inside the hoistway, provided they are in their original sheaths. 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. Liquid-tight flexible nonmetallic conduit, Flexible cords and cables, or conductors grouped together and taped or corded, are permitted without raceway, where they are part of listed equipment, a driving machine or a driving-machine brake, Flexible metal conduit, liquid-tight flexible metal or nonmetallic conduit, 3/8 in. 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. While machine room-less designs have been commercially available for many years, their use may still be unknown to some AHJs. Building codes were deemed necessary to protect the public against shoddy builders and outmoded construction techniques. The panel further clarified that the marked SCCR value must be adequate for the available fault current to ensure a safe installation. To achieve flexibility and endurance, traveling cable is more finely stranded and, where possible, separated into discrete conductors. IAEI News Magazine. In driving through commercialized suburban areas, you frequently see paralleled conductors for large retail grocers (where there is a heavy refrigeration load). You can email the site owner to let them know you were blocked. A traction elevator's equipment room is typically located at the top of the building, directly over or adjacent to the shaft. ASME A17.1, Section 2.2.5, National Electrical Code, Rule 620-85 4. It employs specialists in Mobile, Alabama, and has technical and news correspondents around the world. (Hard-service and junior hard-service are trade names that apply to over 30 types of flexible cord, all beginning with the letter S. They have varying properties, such as oil resistance, and various material compositions for insulation, such as a thermoplastic elastomer. Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. f?3-]T2j),l0/%b (g) Stop Switch in Pits. Conductors supplying a single power transformer are to have an ampacity not less than the nameplate current rating of the power transformer plus all other connected loads. However, space is frequently limited within the shaft and as such many ancillary components (shunt trip circuit breakers, fused disconnects) may need to be located outside of the elevator shaft. All elevator hoistways must be equipped with a sump pit located at the rear of the elevator pit. However, when I've put in elevators, NEC seems to always take a back seat to ANSI, which seems . 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. As we have seen, a limited number of these are approved for elevator locations car, hoistway, pit and machine room. If you specify a rescuvator, you must also specify a disconnect switch with an auxiliary contact that opens when the disconnect arm moves to the open position, but stays closed when the OCPD trips. 23.254.250.15 Section 620.85, GFCI Protection for Personnel, provides that 125-V, single-phase, 15- and 20-amp receptacles installed in pits, hoistways, machinery spaces, machine rooms, escalators and moving walks, and on elevator car tops are to be GFCIs. The electrical system designer calculates the maximum available fault current at the elevator controller. To safeguard the passengers and electrical equipment, ASME A17.12.8.2.3.2 requires the power source to the elevator control panel to shut down prior to the discharge of water from a sprinkler head. After reading this article, you should have learned: Which locations require sepa-rate, dedicated branch circuits Which branch circuits are not to be provided with ground fault circuit interrupter (GFCI) pro-tection Which locations must have one or more duplex receptacles Where overcurrent protection for hoistway, pit and machine-room lighting must be located How unsupported lengths of traveling cables are measured. Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page. When the elevator car is at the top landing, it is the length of cable as measured from the point of suspension on the car to the bottom of the loop. If a hydraulic elevator loses power because a heat detector goes off or for any other reason it could trap occupants for an unpleasant amount of time. 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. Conductors supplying a single motor controller are to have an ampacity not less than the motor controller nameplate current rating plus all other connected loads. See Section 3 of the. 68 | WWW.ELEVATORWORLD.COM | June 2012 Continuing Education . %PDF-1.5 % This is the area within the hoistway beneath the car, and there are occasions when elevator technicians have to work in this area for maintenance and troubleshooting. Many of these are for portable lighting.). 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. Good documentation is of key importance to recalling what decisions were made and why. In these installations, it is best to design the elevator controller so the elevator controller SCCR is adequate for the available fault current. For circuit breakers, time-current curves must be consulted as well as the circuit breaker manufacturers selective coordination tables. GFI Receptacles: GFI receptacles shall be required in all elevator machine rooms, machinery spaces and elevator pit areas. proved for elevator locations - car, hoistway, pit and a-chine roo equireents in Article odify the articles in Chap - ter For eaple, it is stated that the cross-sectional area NEMA 4 : All electrical equipment, located less than 1225 mm (48 in.) Marking the elevator controller short-circuit current rating (SCCR) by the elevator controller manufacturer. . For instance, one method to reduce the available fault current is to add an isolation transformer ahead of the elevator controller. This equipment is restricted to that used in connection with the specific elevator, dumbwaiter, escalator, moving walk, platform lift or stairway chairlift. The fan should be on a dedicated circuit. Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. The code notes that elevator rails or other hoistway equipment are not to be used as the grounding conductor for lightning-protection systems. This clear working space must be 30 in. There are options available to achieve this depending upon the customers needs. 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. The electrical system designer needs to communicate this information to the person responsible for specifying the elevator controller, which is most often the architect. In order to aid enforcement, the panel additionally required marking the available fault current at the elevator controller. Metal grating shall be installed over the hole that sits flush with the pit floor. The architect has a choice of either traction or hydraulic elevators. All Rights Reserved | Contact Us | Privacy Policy. By subscribing, you agree to our User Agreement and Privacy Policy & Cookie Statement. [emailprotected] Get more of Elevator World. First, the ATS signals the elevators that it's about to switch over to emergency power preferably 30 sec or more prior to switching, which allows the elevator controller to bring each elevator cab to the nearest landing and stop, thus protecting the motors and electrical system. However, this can vary depending on building conditions and exterior grade. Personal protective equipment (PPE): Use appropriate PPE to protect body parts within the range of 3-16 in. 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). Jul 15, 2021. Mobile, AL 36606 USA Machine room/control space lighting and receptacles 4. Another important electrical system design consideration for supplying power to multiple elevators is NEC 620.62. Because of this, several manufacturers offer an all-in-one shunt trip elevator disconnect switch that includes all the prewired accessories needed to comply with the various Code sections. The two primary hazards are fire and electric shock or arc flash, although there are others. This lighting and receptacle circuit is separate from the circuit serving the motor. Feeders may be installed within the hoistway where the elevator has a driving-machine motor in the hoistway or on the car or counterweight. In a time when increasing value is placed on even small amounts of real estate, elevator design must strive to configure, efficiently control and drive elements to whatever degree possible, and that is the thinking behind some alternate locations for these structures. Each fused switch or circuit breaker in the panelboard is used as an elevator disconnect. Many professionals believe the NEC is applicable only for voltages over a certain level, but that is not the case. Louisiana State Uniform Construction Code Council adopts the 2014 NEC, Basic three-phase power measurements explained, Safety After the Storm Operating Portable Generators. This is somewhat broader than A17.1-2007/B44-07. 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. Article 620s Definitions section includes two terms that describe spaces not attached to the outside of a hoistway. The next section, 620.36, concerns different systems in one raceway or traveling cable. tC|[S9G?+uJP>&/TOy o PK ! Overcurrent devices protecting these branch circuits are to be located in the machine room or similar location. Working spaces for electrical equipment that may have to be examined, adjusted, serviced or maintained is required in all occupancies in an earlier NEC section, 110.26(A). 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. 836 Troy Schenectady Road Latham, NY 12110 . Elevator power disconnect (with utility feed marking) located in the machine room or other permitted location. As always, the best advice in all instancesdo your homework, communicate often, and document decisions made. 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. Get more of Elevator World. 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. (Cross-sectional areas of conductors are given in Chapter 9, Tables 5 through 8. This, however, can result in a dramatic increase in cost, space availability (lack thereof), and reduced efficiency. Utility-owned electrical structures not directly concerned with electrical generation, transmission and distribution are NEC regulated. David Herres Use the below learning-reinforcement questions to study for the Continuing Education Assessment Exam available online at www.elevatorbooks.com or on page 111 of this issue. Name the principal code other than NEC that pertains to elevator design/installation. What is the definition of the machine room? Why are voltage limitations important? In which areas must live parts be enclosed? Why are feeder demand factors permitted for multiple elevators?