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. 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. This requirement applies to all controllers, disconnecting means and other electrical equipment that may need servicing, inspection or maintenance. Many professionals believe the NEC is applicable only for voltages over a certain level, but that is not the case. This accomplishes two functions. It begins by considering metal and nonmetallic wireways. This clear working space must be 30 in. A single dedicated receptacle supplying a permanently installed sump pump does not have to be a GFCI type. The panel further clarified that the marked SCCR value must be adequate for the available fault current to ensure a safe installation. It states an elevator is permitted to be run by an emergency or standby power system. In these installations, it is best to design the elevator controller so the elevator controller SCCR is adequate for the available fault current. Where voltages exceed 600, a sign reading DANGER HIGH VOLTAGE is required. Both electric and nonelectric elevators are to comply with Article 250, the code article that covers grounding and bonding in general. 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. CLAIMED . All rights reserved. He is saying that each pit requires a separate circuit, in other words "dedicated". 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. Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data. 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). The demand factors are given in Table 620.14, which allows significant reductions as the number of motors is increased. 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. 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. However, when I've put in elevators, NEC seems to always take a back seat to ANSI, which seems . The light switch in the pit must be mounted 42 in. The conductors must be in their original sheaths or grouped together and taped or corded. Provide continuous, non -slip, horizontal rungs every 12" for the full height of the pit ladder. We have circuited the receptacles and lights in the pits to the same circuit. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. 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 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. This website is using a security service to protect itself from online attacks. Many of these are for portable lighting.). For circuit breakers, time-current curves must be consulted as well as the circuit breaker manufacturers selective coordination tables. There are options available to achieve this depending upon the customers needs. These are part of Article 725, Class 1, Class 2 and Class 3 Remote-Control, Signaling, and Power-Limited Circuits. In fact, an entire elevator system for a project is most often designed and specified by the architect who has little understanding of the electrical distribution system. It is worth noting that these NEC terms, used throughout Article 620, have been chosen to correlate with A17.1-2007 usage. By subscribing, you agree to our User Agreement and Privacy Policy & Cookie Statement. As always, the best advice in all instancesdo your homework, communicate often, and document decisions made. 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. NEC Article 620 Part IV, Installation of Conductors, contains key mandates for elevator wiring. NEC Article 620 covers elevators, dumbwaiters, escalators, moving walks, platform lifts and stairway chairlifts. 3. This is somewhat broader than A17.1-2007/B44-07. As such, elevator controller manufacturers should make the effort to rethink their designs to avoid costly system design changes. You are seeing this message for one of three reasons: You have reached your limit of free content. 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 To avoid this situation, designers can specify elevator controls with a safety feature commonly called a rescuvator. 6 Stop Switch in Pits There shall be installed in the pit of each elevator an ASME A17.1 CODE enclosed stop switch or switches meeting the requirements The following material is reprinted with permission from the American of 2.26.2.7 and 2.2.6.1 through 2.2.6.3. (To design and install an elevator for a Class I, Division 1 location would be quite an undertaking.). 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). Motor controllers are permitted outside the spaces specified above. [emailprotected] I've never run into this before. If it kills the son of the owner, the son of that builder shall be put to death.. Dec. 21, 2010. charlie b. Shi Liguang, Yao Lianghong, Luo Zhiqun and Wan Jianru, Constructional Stretch and Hoist-Rope Tension . . 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. hb``` ea``j~p2nfH
'xXg00,/(_ Iq8PDdg-~ s$!XI;Fn0vu
`h`R 1y
0B.":9.@, e`xI;=7O3fvbb8:SC;%O*20] %%EOF
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. 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. above the pit floor, shall: Be weatherproof (NEMA 4). Accordingly, for this application, the minimum size is reduced to 20 AWG for lighting circuits. Part X, Emergency and Standby Power Systems, is simple and straightforward. : inspecting; troubleshooting; observing; etc.) These 29 CFR 1910.146 (c) (8) requirements are: Because of this, there is often a communications gap between the electrical system designer, whose design typically stops at the required elevator disconnecting means, and the architect who designs the elevator system. Cross-sectional areas of wireways are found by multiplying the two interior dimensions.) A traction elevator's equipment room is typically located at the top of the building, directly over or adjacent to the shaft. You need to Subscribe to continuing reading. Thus, the need for door interlock functionality is recognized. 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. 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. The cover shall be secured and level with the pit floor. 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. Good documentation is of key importance to recalling what decisions were made and why. A further requirement concerns elevator-car air-conditioning and heating. This is not the elevator companys responsibility. To achieve flexibility and endurance, traveling cable is more finely stranded and, where possible, separated into discrete conductors. Hydraulic elevators are typically more cost effective and used for buildings up to 5-6 stories. GFI Receptacles: GFI receptacles shall be required in all elevator machine rooms, machinery spaces and elevator pit areas. Finally, typical installations and compliance with all these requirements will be discussed. 4.0 (2 Reviews) (2) CLAIMED . You are seeing this message for one of three reasons: You have reached your limit of free content.
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. Elevator power disconnect (with utility feed marking) located in the machine room or other permitted location. 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. Pit drainage must be designed to eliminate a minimum capacity of 3,000 gallons per hour (or 50 GPM) per elevator car. 354 Morgan Ave. . 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. 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. Flexible cords and cables, or conductors grouped together and taped or corded, are permitted to be installed without a raceway. , !! 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. ^W i word/document.xml=nr]6Id=,_$j9-"Y.iGU\h_}. 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. Hydraulic reservoir characteristic of a hydraulic-piston-operated elevator. Elevator travel is far safer than an automobile trip, and the chance of experiencing disaster is on the order of being struck by lightning in ones own backyard. Please check your entries and try again. 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). wide or the width of the equipment, whichever is greater. 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. In hoistways not longer than 6 ft., these additional wiring methods are permitted: A sump or oil-recovery pump located in the pit is permitted to be cord connected. Conductors supplying more than one motor, motor controller or power transformer are to have an ampacity not less than the sum of the nameplate current ratings of the equipment plus all other connected loads. 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. Hard-service cords are permitted only as flexible connections for the top-of-car operating device or the car-top work light. 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. Receptacle for pumps located in the pit shall be a single non-GFCI and shall be located 6 inches above the lowest landing. Corporate Office 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. After such an event, it is important that the affected worker is able to escape the area and get to help. The disconnecting means must disconnect the elevator from the emergency, standby and normal power systems. For platform lifts and stairway chairlifts, the duty is intermittent. Fireman telephone jacks and telephone cabling are typically sufficient for each of these locations. Mobile, AL 36606 USA (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. All equipment in a machine room-less design is installed within the elevator shaft or exterior compartment near the elevator shaft, including the elevator controller and the elevator disconnecting means. For example, an inadequately supported ceiling fan could fall and cause injury or property damage. 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. Motor feeder short circuit and ground-fault protection must be as required in Article 430, Part V for all motors. ,l7CLHmcX9*F -{Q|^"XL`b1y]$,y *R/2Rn{\xG
L*vMP.uKW,)68]Y}+ FYS1B=Q0S>Hc Nevertheless, the primary NEC focus is on elevators, and the intention is to mitigate the hazards associated with the use of electricity. This is important as the tradition of using only time-current curves for the analysis of overcurrent device operation is usually not sufficient since the time-current curves traditionally stop at 0.01 second (not time zero). These may include: The author would like to recognize Jonathan Kennedy for his assistance in creating this article. The lighting switch shall be located so as to be readily accessible from the pit access door. All rights reserved. In elevators provided with Firefighters' Emergency Operation, a drain or sump pump shall be provided. 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. The light switch for the equipment room must be adjacent to the entrance door on the latch side. The Code provides guidance through regulations to establish requirements. First, it is now clear that elevator controllers must be marked by the manufacturer with their SCCR. 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. 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. 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. Therefore, elevator equipment rooms must maintain a temperature between 50F and 90F. 2.2.6.1 This switch shall be so located as to be acces-sible from the pit access door. Additionally, ampacities of the individual conductors and flame-retardant properties of the overall cable are important factors.