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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 are seeing this message for one of three reasons: You have reached your limit of free content. To achieve flexibility and endurance, traveling cable is more finely stranded and, where possible, separated into discrete conductors. It is further specified the machine-room lighting switch be located at the point of entry. 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. It employs specialists in Mobile, Alabama, and has technical and news correspondents around the world. 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. The light switch shall be located so to be accessible from pit access door. 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). Described below are several work practices that may be used to reduce arc-flash hazards when working on energized equipment: 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. 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. 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. The fan should be on a dedicated circuit. You are seeing this message for one of three reasons: You have reached your limit of free content. Part of the reason that elevator usage is extraordinarily safe is that construction and maintenance are regulated by the wonderfully robust ASME A17.1 2007/CSA B44-07 Safety Code for Elevators and Escalators, which contains overall construction and maintenance requirements everything from seismic mandates to machine-room lighting. For this reason, the NEC provides for adequate working space around electrical equipment that may need to be serviced. 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. Indeed, most elevator accidents involve maintenance workers, yet even theirs is not an excessively dangerous profession. 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. Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page. 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). 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. These may include: The author would like to recognize Jonathan Kennedy for his assistance in creating this article. While machine room-less designs have been commercially available for many years, their use may still be unknown to some AHJs. wide or the width of the equipment, whichever is greater. 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. The light switch in the pit must be mounted 42 in. High-rise buildings pose additional concerns. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. A traditional elevator installation (which includes a machine room) requires access inside the elevator shaft. Hydraulic reservoir characteristic of a hydraulic-piston-operated elevator. Where the elevator shaft and/or equipment room has a sprinkler fire suppression system installed, the elevator Code requires main line power to the elevator be removed prior to the application of water. Your IP: Section 620.62, Selective Coordination, is central to multi-elevator installations and must be closely observed. Sign up for our free e-newsletter. The conduit alone can't act as the grounding means. The code is not concerned with the efficiency or sophistication of equipment that it covers, except insofar as safety (in terms of human injury and property damage) is concerned. All Rights Reserved | Contact Us | Privacy Policy. You can email the site owner to let them know you were blocked. Below is a summary of these new 2017 NEC sections: In order to comply with these requirements a chain of events must occur. ASME A17.1, Section 2.2.5, National Electrical Code, Rule 620-85 4. The basic wiring methods are rigid-metal, rigid nonmetallic or intermediate-metal conduit; electrical metallic or rigid nonmetallic tubing; wireways; or Type MC, MI or AC cable, unless otherwise permitted. The traveling cable or raceway is also permitted to include shielded conductors and/or one or more coaxial cables. Thus, the traveling cable must be supported by a steel supporting member. 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. 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. 2023 Endeavor Business Media, LLC. Requirements for commercial garages per the National Electrical Code. Get more of Elevator World. Flexible cords and cables, or conductors grouped together and taped or corded, are permitted to be installed without a raceway. The drain or sump pump discharge shall be into the sanitary or storm drainage system through an indirect waste connection. Hydraulic elevators comprise a hydraulic reservoir, pump, cylinder, and controller. After such an event, it is important that the affected worker is able to escape the area and get to help. The two primary hazards are fire and electric shock or arc flash, although there are others. You must locate this key switch at the main lobby or at the building fire command center. 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. Other requirements: Spa's and Hot Tubs 1996 NEC 15-20 Amp 120 volt Receptacle Requirements for Dwelling units: All outdoor One. +1-251-479-4514 | [emailprotected], Trkiye Office hb``` ea``j~p2nfH 'xXg00,/(_ Iq8PDdg-~ s$!XI;Fn0vu `h`R 1y 0B.":9.@, e`xI;=7O3fvbb8:SC;%O*20] Part X, Emergency and Standby Power Systems, is simple and straightforward. (f) Illumination of Pits. 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. 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. NEC 2011 also addresses branch circuits for machine room or control room/machinery space or control-space lighting and receptacles. 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. All elevator hoistways must be equipped with a sump pit located at the rear of the elevator pit. Through numerous editions, the NEC has, to a great extent, mitigated the hazards accompanying widespread use of electricity, particularly with respect to elevator technology. See Section 3 of the. The proposals resulted in adding new requirements in the 2017 NEC for: This article will also discuss other Code requirements that include selective coordination for elevators that are supplied by emergency, legally required standby or critical operation power systems or multiple elevators supplied from a single feeder, and shunt tripping of elevators where the elevator equipment room and/or shaft has a fire suppression sprinkler system. As mentioned, traditional installations of a traction or hydraulic elevator include a separate machine room. 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. Depending on your local codes, you can do this by installing heat or smoke detectors within 24 in. 2. 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. Marking the available short-circuit (fault) current on the controller by the equipment installer. (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. Other codes and standards interact with the NEC, and it is necessary to see how they all work together in order to create safe and compliant elevator designs/installations. Elevator power disconnect (with utility feed marking) located in the machine room or other permitted location David Herres David Herres holds a New Hampshire Master Electrician's license and has worked as an electrician in the northern part of that state for many years. 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 basic idea is that there must be a separate, dedicated circuit for car lights, receptacles and ventilation on each car. Fuses: Verify that the correct size, type and capacity are installed. The code notes that elevator rails or other hoistway equipment are not to be used as the grounding conductor for lightning-protection systems. 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 thinking behind this requirement is that the injured worker could have severe hand burns and be unable to operate a conventional doorknob. The sum of the cross-sectional area of the individual conductors in raceways is not to exceed 40% of the interior cross-sectional area of the raceway, except as permitted for wireways. Hammurabi, sixth king of Babylon and creator of the Babylonian Empire, decreed: If a builder builds a house for someone and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death. 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. This room is to be secured against unauthorized access (kept locked). As such, elevator controller manufacturers should make the effort to rethink their designs to avoid costly system design changes. 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. There are options available to achieve this depending upon the customers needs. 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. Nevertheless, the primary NEC focus is on elevators, and the intention is to mitigate the hazards associated with the use of electricity. 354 Morgan Ave. The conductors must be in their original sheaths or grouped together and taped or corded. NEC 70620.85 Smoke detectors to recall elevators on Phase I recall are required to be located on each landing, Flexible cords and cables (same conditions as within hoistways). It employs specialists in Mobile, Alabama, and has technical and news correspondents around the world. Hydraulic elevators are typically more cost effective and used for buildings up to 5-6 stories. 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. 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. In elevators provided with Firefighters' Emergency Operation, a drain or sump pump shall be provided. These conductors may be covered with suitable shielding for telephone, audio, video or higher-frequency communications circuits. David Herres 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.