Something went wrong. 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. Metal grating shall be installed over the hole that sits flush with the pit floor. If the equipment must remain energized to perform work, effective insulation and safe electrical working practices should be observed. 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. 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. He also required GFCI protection for the hard-wired sump pump that did not require it. ASME A17.1, Section 2.2.5, National Electrical Code, Rule 620-85 4. If the smoke detector at the designated landing goes into alarm, the elevator will stop at a predetermined alternate floor, which is usually the floor above the designated floor. 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 idea is quite simple. (A) tells us that the lighting and receptacle (s) for the pit must be on separate circuits. Traditional wiring methods and materials come into play, as always, but it is necessary to rethink their deployment. 4.0 (2 Reviews) (2) CLAIMED . (e) Pit Maintenance. Other terms defined in NEC Article 620 are Control System, Motion Controller, Motor Controller, Operation Controller, Operating Device and Signal Device. 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. For platform lifts and stairway chairlifts, the duty is intermittent. Dec. 21, 2010. The basic rule for conductor fill of a metal wireway, as given in Article 376, is that the sum of the cross-sectional areas of all contained conductors at a cross section of a wireway is not to exceed 20% of the interior cross-sectional area of the wireway. For example, an inadequately supported ceiling fan could fall and cause injury or property damage. Fireman telephone jacks and telephone cabling are typically sufficient for each of these locations. endstream endobj 954 0 obj <. 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. Metallic articles: Remove metallic articles such as watches, chains, bracelets, earrings, belt buckles and keychains before troubleshooting. The conduit alone can't act as the grounding means. The two primary hazards are fire and electric shock or arc flash, although there are others. Accordingly, for this application, the minimum size is reduced to 20 AWG for lighting circuits. Specifically, Section 725.43 provides that overcurrent protection for conductors 14 AWG and larger is to be provided in accordance with the conductor ampacity without applying ampacity adjustment and correction factors. ), a duplex 15A 120-volt receptacle in pit with ground- fault circuit protection and a 15A 120-volt Non GFCI receptacle for the sump pump. Selective coordination is also required for multiple elevators per NEC 620.62. If the disconnecting means is an integral part of the motor controller, it is to be operable without requiring opening of the enclosure. Your elevator supplier will take care of all the wiring and related code requirements for the elevator cab and the various controls. You need to Subscribe to continuing reading. The locking capability is important so during maintenance, the equipment will not be inadvertently energized. It is important to note, that these selective coordination tables can indicate a lack of selective coordination at a given fault current for circuit breakers that do not show overlap on the time-current curves of the circuit breakers. Fuses: Verify that the correct size, type and capacity are installed. No provision is to be made to automatically restore power. NEC 2011 also addresses branch circuits for machine room or control room/machinery space or control-space lighting and receptacles. Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. Marking the available short-circuit (fault) current on the controller by the equipment installer. If you provide your elevators with emergency power, you must run communications wires between the automatic transfer switch (ATS) and the elevator control panel. NEC specifies Hoistway wiring, and doesn't seem to distinguish between hoistway and pit. The disconnecting means is also to be a listed device. They are to be part of listed equipment, a driving machine or a driving-machine brake. Hint: Duct Tape to the Rescue, NEC: Air Conditioning and Refrigerating Equipment Part 5. 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. 2023 Endeavor Business Media, LLC. The disconnecting means must disconnect the elevator from the emergency, standby and normal power systems. 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. hbbd```b``+3dL `Y[gw9`RLJO*A$w$@L`F*{|0 P 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. Traditionally, the electrical system design engineer has given little attention to the elevator controller. Otherwise, specify that the elevator supplier provide a battery back-up unit to power the lights in the event of an outage. Where voltages exceed 600, a sign reading DANGER HIGH VOLTAGE is required. 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). NEMA 4 : All electrical equipment, located less than 1225 mm (48 in.) Personal protective equipment (PPE): Use appropriate PPE to protect body parts within the range of 3-16 in. 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. For instance, one method to reduce the available fault current is to add an isolation transformer ahead of the elevator controller. 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. 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. It begins by considering metal and nonmetallic wireways. The party responsible for procuring the elevator control panel must state the minimum acceptable SCCR or the maximum available fault current where the controller will be installed. 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 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 With heavy use on a hot day, the oil can overheat, causing elevator shutdown. This lighting and receptacle circuit is separate from the circuit serving the motor. [emailprotected] The code notes that elevator rails or other hoistway equipment are not to be used as the grounding conductor for lightning-protection systems. 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. But, building codes had been in existence for many centuries. These 29 CFR 1910.146 (c) (8) requirements are: +90 (216) 348 4876, India Office The disconnecting means is to be an externally enclosed, operable, fused motor circuit switch or circuit breaker capable of being locked in the open position. It is worth noting that these NEC terms, used throughout Article 620, have been chosen to correlate with A17.1-2007 usage. This will normally require you to vent the room with a fire/smoke damper and include smoke detector signals in the control logic. Each of these performs a different function, and the wiring mandates vary accordingly. 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. 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. This website is using a security service to protect itself from online attacks. 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). 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. In order to aid enforcement, the panel additionally required marking the available fault current at the elevator controller. Requirements for commercial garages per the National Electrical Code. (B) Lighting Switch. . Article 620s Definitions section includes two terms that describe spaces not attached to the outside of a hoistway. If we fast forward more than 36 centuries, we see some important new developments in elevator technology. The branch circuit supplying these units is to be similarly dedicated, with the associated overcurrent device located in the machine room or similar location. Additional branch circuits are to supply other utilization equipment not covered above. All rights reserved. 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. Many new buildings are incorporating an elevator design that does not include an equipment room (sometimes called machine room-less elevators). 988 0 obj <>stream Cross-sectional areas of wireways are found by multiplying the two interior dimensions.) This accomplishes two functions. In contrast to the lighting, these receptacles must be connected to GFCI devices. 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. As we have seen, a limited number of these are approved for elevator locations car, hoistway, pit and machine room. 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. h-`7 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. Thus, the traveling cable must be supported by a steel supporting member. 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. 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. 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. These are part of Article 725, Class 1, Class 2 and Class 3 Remote-Control, Signaling, and Power-Limited Circuits. By subscribing, you agree to our User Agreement and Privacy Policy & Cookie Statement. The feeder OCPD needs to remain closed so the remaining elevators have power and continue to function. NEC Guidelines on Commercial Garages. Please check your entries and try again. charlie b. Hydraulic elevators are typically more cost effective and used for buildings up to 5-6 stories. This equipment is restricted to that used in connection with the specific elevator, dumbwaiter, escalator, moving walk, platform lift or stairway chairlift. 1. Adhering to the requirements will ensure a hazard-free electrical installation. 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. 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. Elisha Otis safety elevator, introduced in 1853, prevented the fall of the car if the cable broke. 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. Performance & security by Cloudflare. ASME A17.1 . Another location that requires a separate branch circuit for lighting and receptacle(s) is the hoistway pit. 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. Corporate Office 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. Section 620.43, Location of and Protection for Cables, provides that traveling cable supports are to be located so as to reduce the possibility of damage due to the cables coming in contact with the hoistway construction or equipment in the hoistway to a minimum. (All intentionally grounded elements must be held at equal potential.) 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. Section 620.62, Selective Coordination, is central to multi-elevator installations and must be closely observed. Good documentation is of key importance to recalling what decisions were made and why. Motor feeder short circuit and ground-fault protection must be as required in Article 430, Part V for all motors. NEC has a further note that the term wheelchair lift has been changed to platform lift.. Feeders may be installed within the hoistway where the elevator has a driving-machine motor in the hoistway or on the car or counterweight. This room is to be secured against unauthorized access (kept locked). Fluid pressure in the cylinder raises and lowers the elevator cab. One. As such, elevator controller manufacturers should make the effort to rethink their designs to avoid costly system design changes. 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.