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. Nevertheless, the primary NEC focus is on elevators, and the intention is to mitigate the hazards associated with the use of electricity. Marking the available short-circuit (fault) current on the controller by the equipment installer. NEC Article 620 contains numerous other disconnect provisions, which must be carefully scrutinized prior to design work so the installation is compliant. 2m9 `K]f*F gaR He is saying that each pit requires a separate circuit, in other words "dedicated". Acceptable types of wire for this application are given in Table 400.4, which occurs in an earlier chapter and lists various types of elevator cable for lighting and control in both unclassified and hazardous locations. This requirement applies to all controllers, disconnecting means and other electrical equipment that may need servicing, inspection or maintenance. The two documents are in harmony and should be used in conjunction. First, it is now clear that elevator controllers must be marked by the manufacturer with their SCCR. 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. Suspending the cables from the supports by a means that automatically tightens around the cable when tension is increased for unsupported lengths up to 200 ft. An NEC Informational Note defines unsupported lengths. 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. 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. The lighting is not to be connected to a GFCI, because the elevator car is not a place that should experience nuisance tripping. As always, the best advice in all instancesdo your homework, communicate often, and document decisions made. (ASME has a separate document, A18.1-2008 Safety Standard for Platform Lifts and Stairway Lifts). To avoid this situation, designers can specify elevator controls with a safety feature commonly called a rescuvator. Lights and convenience outlets in elevator pits shall be installed to comply with the requirements of CCR, Title 24, Part 3, Article 620. Mike Holt. Here, the National Electrical Safety Code has jurisdiction. Motor feeder short circuit and ground-fault protection must be as required in Article 430, Part V for all motors. 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). 2.2.2.6 . Dan Neeser is a Senior Field Application Engineer with Eatons Bussmann Division. Next, with multiple elevator banks, the controller will usually allow only one elevator at a time to operate, reducing the amount of emergency power required. 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. 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. wide or the width of the equipment, whichever is greater. +1-251-479-4514 | [emailprotected], Trkiye Office Depending on your local codes, you can do this by installing heat or smoke detectors within 24 in. Hydraulic reservoir characteristic of a hydraulic-piston-operated elevator. 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. IAEI News Magazine. While the definitions are straightforward, their deployment in real-life building projects involves enormous legal and moral implications, given the fact that we are carrying large numbers of people hundreds of feet above the earths surface on a daily basis. 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. Louisiana State Uniform Construction Code Council adopts the 2014 NEC, Basic three-phase power measurements explained, Safety After the Storm Operating Portable Generators. 3. For this reason, the NEC provides for adequate working space around electrical equipment that may need to be serviced. (f) Illumination of Pits. Additionally, ampacities of the individual conductors and flame-retardant properties of the overall cable are important factors. 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. Flexible cords and cables part of listed equipment operating at 30 V (42 VDC) or less, similarly supported and protected, jacketed and flame retardant, are permitted. Pit drainage must be designed to eliminate a minimum capacity of 3,000 gallons per hour (or 50 GPM) per elevator car. It is important for the design engineer to coordinate with the architect to determine the elevator manufacturer basis of design to determine if and when additional power and lighting is required. The branch circuit supplying these units is to be similarly dedicated, with the associated overcurrent device located in the machine room or similar location. Examples of PPE that may be appropriate are non-conductive eye protection, clean leather or fire-resistant gloves, and natural-fiber or fire-resistant-rated long-sleeved shirts and pants, or fire-resistant-rated long-sleeved coveralls. 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. 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. (A) tells us that the lighting and receptacle (s) for the pit must be on separate circuits. (Cross-sectional areas of conductors are given in Chapter 9, Tables 5 through 8. Overload protection for motors is to conform with Article 430, Part III, the general code area that covers motor and branch-circuit overload protection for all motors. Auxilliary gutters are permitted in machine and control rooms between controllers, starters and similar apparatuses. 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. Marking the elevator controller short-circuit current rating (SCCR) by the elevator controller manufacturer. 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. 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. Overcurrent devices protecting these branch circuits are to be located in the machine room or similar location. Special conditions: Troubleshooting in wet, hot or cold conditions calls for extra caution. A single dedicated receptacle supplying a permanently installed sump pump does not have to be a GFCI type. Thus, the need for door interlock functionality is recognized. 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. 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. 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. 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. Requirements in Article 620 modify the articles in Chapter 3. hbbd```b``+3dL `Y[gw9`RLJO*A$w$@L`F*{|0 P Each of these performs a different function, and the wiring mandates vary accordingly. 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 cord is to be a hard-usage, oil-resistant type not over 6 ft. in length. 1. NEC articles generally adhere to a template, which greatly aids in navigating and quickly locating mandates as needed for project design or, on an installation level, in the field. By subscribing, you agree to our User Agreement and Privacy Policy & Cookie Statement. The drain or sump pump discharge shall be into the sanitary or storm drainage system through an indirect waste connection. Such cable groups are to be supported at intervals not over 3 ft. and located so as to be protected from physical damage. The article stands apart from the rest of the code in the sense it exempts these categories of circuits from the general requirements for wiring in most occupancies, found in Chapter 3. 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. 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. 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. Hint: Duct Tape to the Rescue, NEC: Air Conditioning and Refrigerating Equipment Part 5. Dec. 21, 2010. 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. 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.. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. This may include wiring for signals, communication with the car, lighting, heating, air-conditioning and ventilation of the car or hoistway for fire-detecting systems and pit sump pumps. 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. These are the principle NEC 2011 Article 620 mandates. They are to be part of listed equipment, a driving machine or a driving-machine brake. 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. Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page. Firefighters can then use portable telephone handsets in combination with the jacks and cabling. 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. 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. 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. If it kills the son of the owner, the son of that builder shall be put to death.. The traveling cable, of necessity, is exempted. In the event of a breakdown, that phone must automatically call a location staffed 24 hours a day. 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. To achieve flexibility and endurance, traveling cable is more finely stranded and, where possible, separated into discrete conductors. The hazards are external to the equipment enclosure since equipment SCCR testing and evaluation criteria for product standards are most often performed with the enclosure doors closed and latched, and the fault occurring external to the enclosure. For instance, one method to reduce the available fault current is to add an isolation transformer ahead of the elevator controller. 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. Feeders may be installed within the hoistway where the elevator has a driving-machine motor in the hoistway or on the car or counterweight. The pump sends hydraulic fluid from the reservoir to the cylinder, buried deep below the elevator shaft. You'll be responsible for specifying the items related to the fire alarm and some controls, as well as supplying lighting and power to the equipment room and elevator pit. Your elevator supplier will take care of all the wiring and related code requirements for the elevator cab and the various controls. This equipment is restricted to that used in connection with the specific elevator, dumbwaiter, escalator, moving walk, platform lift or stairway chairlift. Please check your entries and try again. This is somewhat broader than A17.1-2007/B44-07. 4.0 (2 Reviews) (2) CLAIMED . The demand factors are given in Table 620.14, which allows significant reductions as the number of motors is increased. , !! As mentioned, traditional installations of a traction or hydraulic elevator include a separate machine room. Limit switches placed throughout the height of the shaft communicate with the controller and stop the cab at each landing. Otherwise, specify that the elevator supplier provide a battery back-up unit to power the lights in the event of an outage. 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. 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). Adhering to the requirements will ensure a hazard-free electrical installation. Get more of Elevator World. (g) Stop Switch in Pits. 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. Motor controllers are permitted outside the spaces specified above. The same figure applies to nonmetallic wireways. N _rels/.rels ( j0@QN/c[ILj]aGzsFu]U ^[x 1xpf#I)Y*Di")c$qU~31jH[{=E~ Other terms defined in NEC Article 620 are Control System, Motion Controller, Motor Controller, Operation Controller, Operating Device and Signal Device. 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. If you can illuminate the pit using lights that are "above the top of the pit" (whatever that . Power for the elevator controller must first enter a lockable safety disconnect device, located adjacent to the door of the equipment room. Traction elevators raise and lower the elevator cab with cables, a pulley system, and counter weights powered by a motor at the main drive wheel. 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). The electrical system designer needs to communicate this information to the person responsible for specifying the elevator controller, which is most often the architect. Sumps and sump pumps in pits, where provided, shall be covered. Also located in this room might be, but not limited to: exhaust fan, cooling unit (depending on local requirements and/or requirements set forth by the individual elevator supplier), lighting, voice and/or data drop serving the elevator cab emergency phone, elevator controller primary fused disconnect, elevator feeder shunt-trip circuit (i.e., shunt-trip circuit breaker), elevator cab lighting fused switch, and convenience receptacle(s). Article 620 follows this pattern by opening, in Section I, General, with a statement of scope and definitions applicable to the topic under consideration. Flexible cords and cables (same conditions as within hoistways). Second, it must be configured so as to eliminate any chance of tangling or chafing against the inner surface of the hoistway or items mounted on it. It states an elevator is permitted to be run by an emergency or standby power system. A traction elevator's equipment room is typically located at the top of the building, directly over or adjacent to the shaft. NEC specifies Hoistway wiring, and doesn't seem to distinguish between hoistway and pit. Where necessary, it is mandated that suitable guards be provided to protect the cables against damage. Flexible cords and cables, or conductors grouped together and taped or corded, are permitted to be installed without a raceway. Part X, Emergency and Standby Power Systems, is simple and straightforward. The idea is quite simple. above the pit floor, shall: Be weatherproof (NEMA 4). Accordingly, for this application, the minimum size is reduced to 20 AWG for lighting circuits. Moreover, it is necessary to consider future worker safety for an indefinite period. In contrast to the lighting, these receptacles must be connected to GFCI devices. On existing or listed equipment, conductors are permitted to be grouped together and taped or corded without being installed in a raceway. Fuses: Verify that the correct size, type and capacity are installed. Some elevator controller manufacturers believe this is an issue for the electrical system designer and installer to address and remedy by adding impedance to the system for lowering the available fault current. It does specify wiring methods allowed, though, in 620. NEC 2011 also addresses branch circuits for machine room or control room/machinery space or control-space lighting and receptacles. Because they need to move and flex, traveling cables are not required to be in a raceway. 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. 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 basic idea is that there must be a separate, dedicated circuit for car lights, receptacles and ventilation on each car. EazyLift Elevators, Stairlifts, Wheelchair Lifts & Ramps. Dont troubleshoot unless you can keep your shoe/boot soles dry. 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. You are seeing this message for one of three reasons: You have reached your limit of free content. The conduit alone can't act as the grounding means. This room is to be secured against unauthorized access (kept locked). Home Articles Elevator World June 2012 Issue NEC Article 620: Elevators, Part 2. This may be countered by providing good machine-room ventilation. Flexible cords and cables in lengths not to exceed 6 ft. of a flame-retardant type and located to be protected from physical damage are permitted in machine rooms without being installed in a raceway. 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.
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