This website is using a security service to protect itself from online attacks. 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. Where necessary, it is mandated that suitable guards be provided to protect the cables against damage. The electrical system designer needs to communicate this information to the person responsible for specifying the elevator controller, which is most often the architect. Overcurrent devices protecting these branch circuits are to be located in the machine room or similar location. Additional branch circuits are to supply other utilization equipment not covered above. 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. 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. GFCIs in Elevator Pits, Receptacles and More Corporate Office 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. The thinking behind this requirement is that the injured worker could have severe hand burns and be unable to operate a conventional doorknob. Modern electronic elevator controls can be sensitive to temperature shifts. You are seeing this message for one of three reasons: You have reached your limit of free content. Elevators with driving machines located on the car or counterweight, or in the hoistway are permitted outside the specified spaces. 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. Required lighting shall not be connected to the load side of a ground-fault circuit interrupter. Luminaires must be lensed or equipped with wire guards to protect the lamps. If the disconnecting means is an integral part of the motor controller, it is to be operable without requiring opening of the enclosure. 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. You are a subscriber that needs to Sign In. The main concern is to ensure that workers may escape to safety in the awful circumstance of an arc-fault event. Part X, Emergency and Standby Power Systems, is simple and straightforward. ,l7CLHmcX9*F -{Q|^"XL`b1y]$,y *R/2Rn{\xG L*vMP.uKW,)68]Y}+ FYS1B=Q0S>Hc While machine room-less designs have been commercially available for many years, their use may still be unknown to some AHJs. (Cross-sectional areas of conductors are given in Chapter 9, Tables 5 through 8. Click to reveal 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. 988 0 obj <>stream 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. 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 elevator controller manufacturer must determine the required elevator controller SCCR as stated in the elevator controller specification and provide an elevator controller SCCR that is equal to or greater than the available fault current thats indicated in the design documents where there are multiple elevator controllers at different locations. 2.2.6.1 This switch shall be so located as to be acces-sible from the pit access door. My reasoning comes from 620.24 (A) and (C). A little more narrowly focused (yet of great consequence) is the ubiquitous NEC, which, in the National Fire Protection Association (NFPA)s venerable Handbook edition, devotes 18 double-column pages to electrical design and installation requirements for elevators, escalators and related equipment. In these installations, it is best to design the elevator controller so the elevator controller SCCR is adequate for the available fault current. 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. Weight (passengers, freight, car and attendant machinery) may be fairly substantial, and speed is significant. Section 620.85, GFCI Protection for Personnel, provides that 125-V, single-phase, 15- and 20-amp receptacles installed in pits, hoistways, machinery spaces, machine rooms, escalators and moving walks, and on elevator car tops are to be GFCIs. 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 ! 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. 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. 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. NEC Article 620 Part V, Traveling Cables, is driven by two major issues. Hint: Duct Tape to the Rescue, NEC: Air Conditioning and Refrigerating Equipment Part 5. 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. With the new elevator controller requirements, more attention will be focused on the elevator system. Through numerous editions, the NEC has, to a great extent, mitigated the hazards accompanying widespread use of electricity, particularly with respect to elevator technology. But by understanding how these items fit together and what purpose they serve, you can have a successful project. I've never run into this before. Pits shall be maintained in a clean and dry condition. NEC Article 620: Elevators, Part 2 - Elevator World, Inc. 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. Sign up for our free e-newsletter. This switch will ensure that the elevator won't descend into the elevator pit and allow maintenance people to work safely in the area beneath the cab. For instance, a typical elevator controller may traditionally have SCCR ratings from 5 to 10 kA. Compliance with the 2017 NEC for Elevator Controllers Motors for traction elevators were traditionally DC or synchronous, but new installations use AC motors and VFDs for speed control. Hydraulic reservoir characteristic of a hydraulic-piston-operated elevator. As such, elevator controller manufacturers should make the effort to rethink their designs to avoid costly system design changes. Since 1953, Elevator World, Inc. has been the premier publisher for the global vertical transportation industry. The Electrical Ups and Downs of Elevator Design | EC&M 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. Fireman telephone jacks and telephone cabling are typically sufficient for each of these locations. Even though Edison grasped the basic ideas of fusing and overcurrent protection, many hazards remained. This may be countered by providing good machine-room ventilation. 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. It is further stressed that no provision is to be made to open or close the disconnecting means from any other part of the premises. ), 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. The branch circuit supplying these units is to be similarly dedicated, with the associated overcurrent device located in the machine room or similar location. Where multiple driving machines are connected to a single elevator, there is to be one disconnecting means to disconnect the motor(s) and control-valve-operating magnets. If you provide your elevators with emergency power, you must run communications wires between the automatic transfer switch (ATS) and the elevator control panel. And so the needs can be very different. Other building loads, such as power and lighting, may function as the energy absorbing means, provided these loads are automatically connected to the emergency or standby power system operating the elevators and large enough to absorb the regenerative power. Selective coordination is also required for multiple elevators per NEC 620.62. 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. First, the traveling cable must be composed of very fine-stranded conductors so it can flex with a minimum of internal stresses, ensuring long service life and reliability. Home Articles Elevator World June 2012 Issue NEC Article 620: Elevators, Part 2. It is further stated that the disconnecting means are not to disconnect the branch circuits required in sections 620.22, 620.23 and 620.24. Home Articles Elevator World April 2012 Issue NEC Article 620: Elevators, Part I. 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. Machine room/control space lighting and receptacles 4. 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. This is typically accomplished via a shunt trip device. See Section 3 of the. The cord is to be a hard-usage, oil-resistant type not over 6 ft. in length. One way to achieve this is by paralleling wires, i.e., connecting the runs at both ends so they are physically like two wires but electrically one. 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. 2.2.2.6 . With heavy use on a hot day, the oil can overheat, causing elevator shutdown. Apr 24, 2013. correct me if I'm wrong, but I believe it's damp. 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. 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.. The disconnecting means must disconnect the elevator from the emergency, standby and normal power systems. Such vehicles include, but are not . Personal protective equipment (PPE): Use appropriate PPE to protect body parts within the range of 3-16 in. 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. Provide continuous, non -slip, horizontal rungs every 12" for the full height of the pit ladder. Please check your entries and try again. 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. Elevator PITS | Mike Holt's Forum The electrical energy does not traverse the human body, but proximity to the explosion means severe injury is possible from the intense heat and concussive shockwave. IAEI News Magazine. To avoid this situation, designers can specify elevator controls with a safety feature commonly called a rescuvator. This is somewhat broader than A17.1-2007/B44-07. [emailprotected] No provision is to be made to automatically restore power. This clear working space must be 30 in. 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. endstream endobj startxref 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). 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)]. 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. They must be in enclosures with doors or removable panels that can be locked in the closed position. 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. Elevator Pit Drain or Sump Pump | UpCodes Motor feeder short circuit and ground-fault protection must be as required in Article 430, Part V for all motors. Section 620.62, Selective Coordination, is central to multi-elevator installations and must be closely observed. Similar provisions are attached to elevator-car heating and air-conditioning disconnecting means, and to other utilization equipment. 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. Hydraulic reservoir characteristic of a hydraulic-piston-operated elevator. A single dedicated receptacle supplying a permanently installed sump pump does not have to be a GFCI type. +90 (216) 348 4876, India Office NEMA 4 : All electrical equipment, located less than 1225 mm (48 in.) Feeders may be installed within the hoistway where the elevator has a driving-machine motor in the hoistway or on the car or counterweight. ), advise the building owner to correct the condition. Marking the elevator controller short-circuit current rating (SCCR) by the elevator controller manufacturer. 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. Utility-owned electrical structures not directly concerned with electrical generation, transmission and distribution are NEC regulated. We resume with a look at wiring methods, overcurrent protection, grounding and other NEC provisions as they relate to these installations. A further requirement concerns elevator-car air-conditioning and heating. Fluid pressure in the cylinder raises and lowers the elevator cab. 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. High-rise buildings pose additional concerns. The light switch for the equipment room must be adjacent to the entrance door on the latch side. NEC Guidelines on Commercial Garages. Flexible metal, liquid-tight flexible metal or liquid-tight flexible nonmetallic conduit 3/8 in. +90 (216) 348 4876, India Office [emailprotected] Design practices that are acceptable in some jurisdictions may not be in others. 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. The code exempts some fairly broad areas where compliance is not expected. 2. NEC Guidelines on Commercial Garages | EC&M The demand factors are given in Table 620.14, which allows significant reductions as the number of motors is increased. This is because the material may contribute fuel to a fire that has originated elsewhere. Many professionals believe the NEC is applicable only for voltages over a certain level, but that is not the case. Even non-composite fiber-optic cable, which does not carry electrical energy, is subject to the code. +1-251-479-4514 | [emailprotected], Trkiye Office If you can illuminate the pit using lights that are "above the top of the pit" (whatever that . 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. We have circuited the receptacles and lights in the pits to the same circuit. Many NEC articles address voltage limitations, and Article 620 is no exception. You must locate this key switch at the main lobby or at the building fire command center. Finally, typical installations and compliance with all these requirements will be discussed. Inspecting Elevator Power Wiring - IAEI Magazine Follow the manufacturers instructions and precautions. Part II of Article 620 concerns conductors used in elevator work, and several important requirements are covered. of the sprinkler heads. 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). Both electric and nonelectric elevators are to comply with Article 250, the code article that covers grounding and bonding in general. 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. 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. They are to be part of listed equipment, a driving machine or a driving-machine brake. 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. Fuses: Verify that the correct size, type and capacity are installed. The basic idea is that there must be a separate, dedicated circuit for car lights, receptacles and ventilation on each car. All rights reserved. Where voltages exceed 600, a sign reading DANGER HIGH VOLTAGE is required. 3. Article 620 follows this pattern by opening, in Section I, General, with a statement of scope and definitions applicable to the topic under consideration. Cylinders in hydraulic elevators usually aren't suitable for buildings taller than five stories. The elevator pit discharge system is not required to include an oil separator, except as required by section 1003.4. Where a feeder powers more than one elevator, you need selective coordination; the OCPDs must be series-designed so a fault at one of the elevators will be cleared by only the OCPD serving it. It employs specialists in Mobile, Alabama, and has technical and news correspondents around the world. Shi Liguang, Yao Lianghong, Luo Zhiqun and Wan Jianru, Constructional Stretch and Hoist-Rope Tension . Firefighters can then use portable telephone handsets in combination with the jacks and cabling. 23.254.250.15 Something went wrong. In order to aid enforcement, the panel additionally required marking the available fault current at the elevator controller. It is further specified the machine-room lighting switch be located at the point of entry. 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. This accomplishes two functions. Accordingly, the supply wires are protected only for short circuit, and the overload protection is provided closer to the motor. Upon loss of power, the rescuvator controls the cab, lowers it to the designated floor, and opens its doors. For example, an inadequately supported ceiling fan could fall and cause injury or property damage. Frequently Encountered Items That Delay Accep Tance of New Elevators When you're designing an electrical system for a building, don't let elevator requirements bring you down. This equipment is restricted to that used in connection with the specific elevator, dumbwaiter, escalator, moving walk, platform lift or stairway chairlift. The locking capability is important so during maintenance, the equipment will not be inadvertently energized. Though I understand how someone might argue two. After such an event, it is important that the affected worker is able to escape the area and get to help. h-`7 These requirements, found in Article 620 (part of Chapter 6, Special Equipment), are in addition to NEC Chapters 1-3, which stipulate general wiring protocols applicable in most residential, commercial and industrial venues. In Part One of this series (ELEVATOR WORLD, April 2012), we began an examination of National Electrical Code (NEC) 2011 mandates for elevators and related equipment installations. 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. With these new NEC requirements, there is now the potential that an elevator controller SCCR may be required thats higher than what elevator manufacturers have historically furnished. You need to Subscribe to continuing reading. Part III, Wiring, looks at the types of wiring that may be installed in hoistways, cars, machine rooms and related spaces. 836 Troy Schenectady Road ; Latham, NY 12110 . Nevertheless, the primary NEC focus is on elevators, and the intention is to mitigate the hazards associated with the use of electricity. Cross-sectional areas of conduits are given in Chapter 9, Table 4. These 29 CFR 1910.146 (c) (8) requirements are: +91 8025357028, 2022 Elevator World, LLC. Such design innovations require sophisticated wiring strategies. endstream endobj 954 0 obj <. But the lights don't have to be in the pit itself. 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 sump pump/drain shall have the capacity to remove a minimum of 11.4 m. 3 /h (3,000 gal/h) per elevator. Elisha Otis safety elevator, introduced in 1853, prevented the fall of the car if the cable broke. Supports for cables or raceways in a hoistway or in an escalator or moving-walk wellway or platform lift and stairway chairlift runway must be securely fastened to the guide rail, escalator or moving-walk truss, or to the hoistway, wellway or runway construction. 3016. Pits for Elevators. - California Department of Industrial Relations PDF Electric Elevator Checklist Cover Page - Oregon Accordingly, for this application, the minimum size is reduced to 20 AWG for lighting circuits. f?3-]T2j),l0/%b 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. Below is a summary of these new 2017 NEC sections: In order to comply with these requirements a chain of events must occur.