Article 620 follows this pattern by opening, in Section I, General, with a statement of scope and definitions applicable to the topic under consideration. Metallic articles: Remove metallic articles such as watches, chains, bracelets, earrings, belt buckles and keychains before troubleshooting. 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. See Section 3 of the. CLAIMED . The light switch for the equipment room must be adjacent to the entrance door on the latch side. They must be in enclosures with doors or removable panels that can be locked in the closed position. 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. Hoistway door interlock wiring from the riser must be flame retardant and have insulation suitable for a temperature not less than 200C (392F), much higher than that required for most raceway or cable applications. PK ! %PDF-1.5 % Pit light with guard (ten foot candles min. It is mandatory, as in the car, that these items have a separate, dedicated branch circuit, and the required lighting is not to be supplied through a GFCI. For example, an inadequately supported ceiling fan could fall and cause injury or property damage. 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. Article 620s Definitions section includes two terms that describe spaces not attached to the outside of a hoistway. The light switch shall be located so to be accessible from pit access door. Traditional wiring methods and materials come into play, as always, but it is necessary to rethink their deployment. The conduit alone can't act as the grounding means. Machine room-less elevator installations incorporate the elevator controller and often the primary disconnecting means in a convenient package that is located within the elevator shaft. The disconnecting means is also to be a listed device. They are differentiated from other similar structures by the fact that they are not attached to the outside perimeter or surface of the walls, ceiling or floor of the hoistway. One. Hint: Duct Tape to the Rescue, NEC: Air Conditioning and Refrigerating Equipment Part 5. The basic idea is that there must be a separate, dedicated circuit for car lights, receptacles and ventilation on each car. For just $7.99 per month, you can gain access to more than 5,000 articles from all Elevator World Publications, this includes EW Global, EW Europe, EW India, EW Middle East, EW Turkey, and EW UK. While machine room-less designs have been commercially available for many years, their use may still be unknown to some AHJs. 2m9 `K]f*F gaR 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. 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. For platform lifts and stairway chairlifts, the duty is intermittent. 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). Generally, it is decreed that the supply voltage is not to exceed 300 V between conductors (allowing for the familiar 240-V concept), although there are exceptions. Another location that requires a separate branch circuit for lighting and receptacle(s) is the hoistway pit. 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 elevator equipment room that serves a hydraulic elevator is almost always located on the lowest floor adjacent to the elevator shaft. Always verify all conditions and requirements with the state and the AHJ where the installation is taking place. You must run a separate insulated grounding conductor with the feeder conductors from the electrical source to the elevator controller. 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. The elevator pit discharge system is not required to include an oil separator, except as required by section 1003.4. +90 (216) 348 4876, India Office Notwithstanding, if sprinklers are installed in hoistways, machine rooms or the like, the disconnecting means is permitted to automatically open the power supply to the affected elevator(s) prior to the application of water. A raceway that comes loose on the inside of a hoistway could catch on a moving car, causing immense damage and hazard to users. He is saying that each pit requires a separate circuit, in other words "dedicated". 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. Use the below learning-reinforcement questions to study for the Continuing Education Assessment Exam available online at www.elevatorbooks.com or on page 81 of this issue. Which equipment requires a separate branch circuit in the elevator car? Is lighting required to be GFCI protected in the machine room? Where is the lighting switch to be located in the machine room? What is the maximum raceway conductor fill in an elevator hoistway? How many disconnecting means are required for an elevator power supply? The NEC rule specifies that the minimum size for paralleled conductors is 1/0 AWG, which is much too big for an elevator traveling cable. The usual scenario for electrical injury is shock when electrical current passes through the human body. Installing electrical equipment where its SCCR is less than the available short-circuit current creates serious safety hazards. 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. The drain or sump pump discharge shall be into the sanitary or storm drainage system through an indirect waste connection. These are part of Article 725, Class 1, Class 2 and Class 3 Remote-Control, Signaling, and Power-Limited Circuits. The fire loading resulting from an accumulation of abandoned low-voltage cabling may be considerable, and has to be understood and dealt with. 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. PDF C.1 General Requirements for All Elevator Installations Smoke detectors, which are required in all elevator lobbies and elevator equipment rooms, must be connected to the elevator controllers directly by means of auxiliary contacts and wiring, or indirectly by means of output signals from the fire alarm control panel. As greater numbers of elevators are added, the likelihood of them all operating simultaneously decreases so that it is permissible to reduce the feeder ampacity. Otherwise, specify that the elevator supplier provide a battery back-up unit to power the lights in the event of an outage. 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. 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. 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. Guidance in determining whether elevator pits meet the definition of 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. 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. Shi Liguang, Yao Lianghong, Luo Zhiqun and Wan Jianru, Constructional Stretch and Hoist-Rope Tension . The traveling cable or raceway is also permitted to include shielded conductors and/or one or more coaxial cables. It is worth mentioning that when 600 V is talked about as a limit in the NEC, it is generally meant that the familiar 600-V nominal-voltage system is considered to lie within the permitted zone, making it a common usage. endstream endobj 954 0 obj <. 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. For instance, one method to reduce the available fault current is to add an isolation transformer ahead of the elevator controller. Elevator Pit Sump Pump Electrical Requirements Hard-service cords are permitted only as flexible connections for the top-of-car operating device or the car-top work light. f?3-]T2j),l0/%b As such, elevator controller manufacturers should make the effort to rethink their designs to avoid costly system design changes. All rights reserved. (To design and install an elevator for a Class I, Division 1 location would be quite an undertaking.). You are seeing this message for one of three reasons: You have reached your limit of free content. Many of these are for portable lighting.). 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. For example, wiring that is under exclusive utility control and has to do with the generation and distribution of electrical power is not NEC regulated. 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. If the equipment must remain energized to perform work, effective insulation and safe electrical working practices should be observed. PDF NEC Article 0: Elevator art Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. Motor controllers are permitted outside the spaces specified above. Apr 24, 2013. correct me if I'm wrong, but I believe it's damp. First, you'll need to install lighting in the elevator equipment room (Photo 1) and shaft pit (Photo 2). They are to be part of listed equipment, a driving machine or a driving-machine brake. This is typically accomplished via a shunt trip device. 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. These may include: The author would like to recognize Jonathan Kennedy for his assistance in creating this article. 1. Any other utilization equipment associated with the elevator NEC Article 620 Part VI, Disconnecting Means and Control, is rather exacting. We resume with a look at wiring methods, overcurrent protection, grounding and other NEC provisions as they relate to these installations. You need at least one 120VAC GFCI-protected receptacle at each location. It states an elevator is permitted to be run by an emergency or standby power system. Machine room/control space lighting and receptacles 4. or larger, not over 6 ft. in length. Loss of voltage to the control circuit for the disconnecting means shall cause a supervisory signal to be indicated at the control unit and required remote annunciation. 0 Metal grating shall be installed over the hole that sits flush with the pit floor. It is further specified the machine-room lighting switch be located at the point of entry. If power is not being supplied to the elevator controller (e.g., open mainline fuses, etc. NEMA 4 : All electrical equipment, located less than 1225 mm (48 in.) It is important, where mandated, that there be no more than a single disconnecting means, so if emergency action is required, first responders will not be able to power down the equipment from one location. 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. The disconnecting means must disconnect the elevator from the emergency, standby and normal power systems. Choose topics from a full list of courses covering electrical topics that cover what you need to know from the NEC and other electrical codes and standards. Here again, the lighting is not to be connected to a GFCI, whereas such protection is required for the receptacle(s). hbbd```b``+3dL `Y[gw9`RLJO*A$w$@L`F*{|0 P The circuit(s) for the lighting and receptacles must be dedicated to the elevator area only. 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. A further requirement concerns elevator-car air-conditioning and heating. from the exposed components, and the incident energy calculated at 18 in. Motors for traction elevators were traditionally DC or synchronous, but new installations use AC motors and VFDs for speed control. NEC 70620.85 Smoke detectors to recall elevators on Phase I recall are required to be located on each landing, Accordingly, the supply wires are protected only for short circuit, and the overload protection is provided closer to the motor. The various items to consider and check when designing for elevator installations have many potential pitfalls. This is somewhat broader than A17.1-2007/B44-07. Similarly, the integrity of the traveling cable is emphasized. To avoid this situation, designers can specify elevator controls with a safety feature commonly called a rescuvator. ASME A17.1, Section 2.2.5, National Electrical Code, Rule 620-85 4. 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. 354 Morgan Ave. However, when I've put in elevators, NEC seems to always take a back seat to ANSI, which seems . Marking the available short-circuit (fault) current on the controller by the equipment installer. This room is to be secured against unauthorized access (kept locked). If this is not done and the available fault current exceeds the elevator controller SCCR, other solutions to reduce fault current must be reviewed or equipment changes and field evaluations may be needed. (ASME has a separate document, A18.1-2008 Safety Standard for Platform Lifts and Stairway Lifts). After reading this article, you should have learned about: The meanings of definitions for control room and control space versus machine room The purpose and specifications for working spaces Insulation types and minimum sizes of conductors Requirements for feeder and branch-circuit conductors Feeder demand factors for ele-vators. The basic requirement is for minimum clear distances of various depths for equipment operating at 600 V or less, nominal, depending upon voltage to ground and lateral distance to insulated or grounded surfaces or exposed live parts (not an issue in elevator machine rooms). Marking the elevator controller short-circuit current rating (SCCR) by the elevator controller manufacturer. The Electrical Ups and Downs of Elevator Design | EC&M In elevators provided with Firefighters' Emergency Operation, a drain or sump pump shall be provided. All Rights Reserved | Contact Us | Privacy Policy. Section 620.37 re-emphasizes that only wiring used in connection with the elevator is permitted within the hoistway, machine room, control room/machinery space or control space. It employs specialists in Mobile, Alabama, and has technical and news correspondents around the world. Flexible cords and cables (same conditions as within hoistways). 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. Mobile, AL 36606 USA [emailprotected] The code exempts some fairly broad areas where compliance is not expected. It begins by considering metal and nonmetallic wireways. Many new buildings are incorporating an elevator design that does not include an equipment room (sometimes called machine room-less elevators). Since 1953, Elevator World, Inc. has been the premier publisher for the global vertical transportation industry. 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. NEC has a further note that the term wheelchair lift has been changed to platform lift.. NEC Article 620: Elevators, Part I - Elevator World, Inc. The condition is that all conductors must be insulated for the maximum voltage applied to any conductor within the cables or raceway system, and all live parts of the equipment must be insulated from ground for this maximum voltage. . It provides that where more than one driving-machine disconnecting means is supplied by a single feeder, the overcurrent protective devices in each disconnecting means are to be selectively coordinated with any other supply side overcurrent protective devices. 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. 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. 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)]. The simplest option is to use a shunt trip circuit breaker in either the feeder supplying the elevator or the elevator disconnect. In the event of a breakdown, that phone must automatically call a location staffed 24 hours a day. To achieve flexibility and endurance, traveling cable is more finely stranded and, where possible, separated into discrete conductors. 1993 NEC 15-20 Amp 120 volt Receptacle Requirements: Wet bar sinks, all bathrooms, roof tops, elevator machines rooms, elevator car tops, elevator pits. These circuit breaker selective coordination tables can be used to identify the maximum fault current that a pair of circuit breakers can selectively coordinate. Convenience receptacles and lighting for maintenance purposes are required at the base of the pit and, in some instances (elevator manufacturer dependent), at the top of the elevator shaft. You need to Subscribe to continuing reading. Elevator Pit Drain or Sump Pump | UpCodes 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. 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. There are options available to achieve this depending upon the customers needs. Design practices that are acceptable in some jurisdictions may not be in others. I've never run into this before. As mentioned, traditional installations of a traction or hydraulic elevator include a separate machine room. 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 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. The reason the NEC CMP 12 added these requirements, as shown in the panel statements, directly relates to the concern that elevator controllers can be installed in locations where the available fault current can be high and the inspector may not be able to clearly determine the SCCR of the elevator controller unless it is marked on the equipment. Both electric and nonelectric elevators are to comply with Article 250, the code article that covers grounding and bonding in general. Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page. This requirement applies to all controllers, disconnecting means and other electrical equipment that may need servicing, inspection or maintenance. Get more of Elevator World. Society of Mechanical Engineers. Hydraulic elevators are typically more cost effective and used for buildings up to 5-6 stories. The disconnecting means is to be in the machine room or similar location, with provision for being locked in the open position. Dan Neeser is a Senior Field Application Engineer with Eatons Bussmann Division. 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. Home Articles Elevator World April 2012 Issue NEC Article 620: Elevators, Part I. Hoistway pit lighting and receptacles 5. Elevator cab lights require emergency back-up power. The floor specified as the designated landing, which must be approved by the Fire Marshal, is usually the floor on grade level so passengers can quickly exit to the outside. They are to be located so as to be protected from physical damage, are to be of a flame-retardant type, and must be part of listed equipment, a driving machine or a driving-machine brake. Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. 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. Sign up for our free e-newsletter. 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. 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. Lights and convenience outlets in elevator pits shall be installed to comply with the requirements of CCR, Title 24, Part 3, Article 620. 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. Fluid pressure in the cylinder raises and lowers the elevator cab. The electrical system designer needs to communicate this information to the person responsible for specifying the elevator controller, which is most often the architect. An example would be the elevator, as well as all wiring in a utility-owned administration building. Granle is a licensed professional engineer with Sebesta Blomberg & Associates, Rochester, Minn. https://www.facebook.com/ElectricalConstructionMaintenanceMagazine, https://www.linkedin.com/company/electrical-construction-maintenance/, ABCs Construction Backlog Indicator Down to Start 2023, The Most Popular Code Quizzes of the Week from 2021, The 10 Most Popular Photo Galleries of 2021, Whats Wrong Here? The main concern is to ensure that workers may escape to safety in the awful circumstance of an arc-fault event. Section 620.62, Selective Coordination, is central to multi-elevator installations and must be closely observed. A second door is required if the equipment is rated over 1200 amps and over 6 ft. wide. endstream endobj startxref 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.. 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. Proper selective coordination in a multi-elevator installation on the same feeder ensures if one elevator develops a fault, the other units will not be shut down. Additionally, ampacities of the individual conductors and flame-retardant properties of the overall cable are important factors. !>x=yy Bvv8?~e PK ! Selective coordination is also required for multiple elevators per NEC 620.62. 2.2.6.1 This switch shall be so located as to be acces-sible from the pit access door. The idea is quite simple. Where necessary, it is mandated that suitable guards be provided to protect the cables against damage. 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. 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. The demand factors are given in Table 620.14, which allows significant reductions as the number of motors is increased. (All intentionally grounded elements must be held at equal potential.) In contrast to the lighting, these receptacles must be connected to GFCI devices. , !! GET YOUR CEUS TODAY, 1998-2021. As always, the best advice in all instancesdo your homework, communicate often, and document decisions made. Instruments: Use category III multimeters and be familiar with their use and limitations. Utility-owned electrical structures not directly concerned with electrical generation, transmission and distribution are NEC regulated. Sumps and sump pumps in pits, where provided, shall be covered. 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. NEC 620.62 requires the elevator disconnecting means (fused switch or circuit breaker) to selectively coordinate with all supply-side overcurrent devices. And so the needs can be very different. PDF Electric Elevator Checklist Cover Page - Oregon If your specifications require a vent at the top of the shaft for venting smoke, you must provide a key switch with a pilot light to control that vent. 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. Additionally, duty on elevator and dumbwaiter motors is rated as intermittent, whereas duty on escalator and moving-walk motors is considered continuous. (B) Lighting Switch. Many people use portable generators until power is restored.