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. z!0: - [Content_Types].xml ( n0EUb*>-RxV=QUAl"93dFk%Y?l}MGDV hbbd```b``+3dL `Y[gw9`RLJO*A$w$@L`F*{|0 P Therefore, elevator equipment rooms must maintain a temperature between 50F and 90F. A clean and dry elevator pit and machine/control room provided (ASME A17.1 Rule 2.1.2) Machine/control room meets manufacturer's requirement of preserving ambient temperature control and humidity (ASME A17.1 Rule 2.7.9) Elevator floor covering installed with appropriate smoke and flame spread (ASME A17.1 Rule 2.14.2) On existing or listed equipment, conductors are permitted to be grouped together and taped or corded without being installed in a raceway. Here again, the lighting is not to be connected to a GFCI, whereas such protection is required for the receptacle(s). Otherwise, specify that the elevator supplier provide a battery back-up unit to power the lights in the event of an outage. 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. High-rise buildings pose additional concerns. 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. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data. 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. Moreover, it is necessary to consider future worker safety for an indefinite period. The cover shall be secured and level with the pit floor. The fire loading resulting from an accumulation of abandoned low-voltage cabling may be considerable, and has to be understood and dealt with. Additional branch circuits are to supply other utilization equipment not covered above. The two documents are in harmony and should be used in conjunction. Therefore, there will be two signals to the elevator control panel related to smoke detectors: one from the designated floor smoke detector and another combined signal from the smoke detectors at the other lobby landings and in the equipment room. 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. Traditional wiring methods and materials come into play, as always, but it is necessary to rethink their deployment. ,l7CLHmcX9*F -{Q|^"XL`b1y]$,y *R/2Rn{\xG L*vMP.uKW,)68]Y}+ FYS1B=Q0S>Hc The electrical system designer needs to communicate this information to the person responsible for specifying the elevator controller, which is most often the architect. 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. 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. This will normally require you to vent the room with a fire/smoke damper and include smoke detector signals in the control logic. 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. ), advise the building owner to correct the condition. With the elevator car at the bottom landing, it is the length of cable as measured from the point of suspension in the hoistway to the bottom of the loop. It does specify wiring methods allowed, though, in 620. 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. A section on branch circuits for car lighting, receptacles, ventilation, heating and air-conditioning contains a number of important provisions. You may go up to 600 V for power circuits supplying door-operator controllers and door motors, branch circuits and feeders to motor controllers, driving-machine motors, machine brakes and motor-generator sets. 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. By subscribing, you agree to our User Agreement and Privacy Policy & Cookie Statement. This is because the material may contribute fuel to a fire that has originated elsewhere. Through numerous editions, the NEC has, to a great extent, mitigated the hazards accompanying widespread use of electricity, particularly with respect to elevator technology. Limit switches placed throughout the height of the shaft communicate with the controller and stop the cab at each landing. 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. Car lighting, receptacles and ventilation 2. This is typically accomplished via a shunt trip device. Good documentation is of key importance to recalling what decisions were made and why. 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. Modern electronic elevator controls can be sensitive to temperature shifts. A second door is required if the equipment is rated over 1200 amps and over 6 ft. wide. 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. Elevator Pit Sump Pump Electrical Requirements By Nat July 30, 2022 Bulls Eye (Simplex) Receptacles: Bulls eye (simplex) receptacle for Sump pumps (now not - GFI) on a delegated circuit will be required in all elevator pits for the elevator pit sump pump. NEC Article 620 contains numerous other disconnect provisions, which must be carefully scrutinized prior to design work so the installation is compliant. 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. Other requirements: Spa's and Hot Tubs 1996 NEC 15-20 Amp 120 volt Receptacle Requirements for Dwelling units: All outdoor In the event of a breakdown, that phone must automatically call a location staffed 24 hours a day. Sumps and sump pumps in pits, where provided, shall be covered. Part II of Article 620 concerns conductors used in elevator work, and several important requirements are covered. 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. Elevators with driving machines located on the car or counterweight, or in the hoistway are permitted outside the specified spaces. As an installer and an inspector, one common issue I've seeen is incompatible connections associated with raceways connections and fittings. Feeder and branch-circuit conductors are required to have specified ampacities: Feeder conductors of less ampacity are permitted for group installations and quite common in elevator work. 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. In case of emergency, electricians, maintenance personnel and any elevator technicians called in to the premises should have ready access to the key. These must also be insulated for the maximum voltage applied to any conductor within the cable or raceway system. Metal grating shall be installed over the hole that sits flush with the pit floor. The disconnecting means is to be located adjacent to or an integral part of the motor controller. If you provide your elevators with emergency power, you must run communications wires between the automatic transfer switch (ATS) and the elevator control panel. This clear working space must be 30 in. The proposals resulted in adding new requirements in the 2017 NEC for: Marking the elevator controller short-circuit current rating (SCCR) by the elevator control-ler manufacturer. You are a subscriber that needs to Sign In. Loss of voltage to the control circuit for the disconnecting means shall cause a supervisory signal to be indicated at the control unit and required remote annunciation. 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. Electricity is often one of the initial services to fail during a storm. It begins by considering metal and nonmetallic wireways. Traveling cables are to be approved for hazardous locations and must comply with the appropriate sections for each hazardous-location class that covers use of flexible cords. (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. 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. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. 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 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. Guarding: Where possible, install temporary guarding to protect from inadvertent contact. 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. The disconnecting means is to be in the machine room or similar location, with provision for being locked in the open position. Thus, the traveling cable must be supported by a steel supporting member. All Rights Reserved | Contact Us | Privacy Policy. All Rights Reserved | Contact Us | Privacy Policy. Hydraulic reservoir characteristic of a hydraulic-piston-operated elevator. 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. A traditional elevator installation (which includes a machine room) requires access inside the elevator shaft. NEC 2011 also addresses branch circuits for machine room or control room/machinery space or control-space lighting and receptacles. 23.254.250.15 The simplest option is to use a shunt trip circuit breaker in either the feeder supplying the elevator or the elevator disconnect. Traditionally, the electrical system design engineer has given little attention to the elevator controller. +90 (216) 348 4876, India Office 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. %%EOF It states an elevator is permitted to be run by an emergency or standby power system. Follow the manufacturers instructions and precautions. Traction elevators are typically faster and more energy efficient than hydraulic elevators, and are often used for high-rise buildings. This is especially true in an elevator shaft where measures have to be taken to ensure that a hazardous situation is not created. 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. (f) Illumination of Pits. Something went wrong. 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. IAEI News Magazine. 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. A further requirement concerns elevator-car air-conditioning and heating. For instance, a typical elevator controller may traditionally have SCCR ratings from 5 to 10 kA. These are covered for generic, non-elevator specific use in earlier articles, 376 and 378, in Chapter 3, Wiring Methods and Materials. 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. 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. 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. It is mandatory, as in the car, that these items have a separate, dedicated branch circuit, and the required lighting is not to be supplied through a GFCI. In such cases, it's economically justifiable to specify a traction type elevator. 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. An exception provides that liquid-tight flexible metal conduit or liquid-tight flexible nonmetallic conduit 3/8 in. Flexible cords and cables (same conditions as within hoistways). NEC 70620.85 Smoke detectors to recall elevators on Phase I recall are required to be located on each landing, 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. 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. Three wiring categories within hoistways are allowed in addition, each with exceptions. endstream endobj 954 0 obj <. Hazards created by water, snow or condensation in the work area can cause slips, falls and accidental contact. 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. All rights reserved. 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. Heating and air-conditioning equipment located on the car must not be in excess of 600 V. All live parts of electrical apparatuses are to be enclosed to protect workers and the public against accidental contact. Both electric and nonelectric elevators are to comply with Article 250, the code article that covers grounding and bonding in general. charlie b. 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. Each of these performs a different function, and the wiring mandates vary accordingly. Traveling cables are to be supported by one of these means: Looping the cables around supports for unsupported lengths less than 100 ft. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. 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. 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. The lighting switch shall be located so as to be readily accessible from the pit access door. 836 Troy Schenectady Road ; Latham, NY 12110 . 3. Motor controllers are permitted outside the spaces specified above. 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. Home Articles Elevator World June 2012 Issue NEC Article 620: Elevators, Part 2. 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. (A) Separate Branch Circuit. The electrical system designer calculates the maximum available fault current at the elevator controller. The feeder OCPD needs to remain closed so the remaining elevators have power and continue to function. Pit drainage must be designed to eliminate a minimum capacity of 3,000 gallons per hour (or 50 GPM) per elevator car. These may include: The author would like to recognize Jonathan Kennedy for his assistance in creating this article. Lights and convenience outlets in elevator pits shall be installed to comply with the requirements of CCR, Title 24, Part 3, Article 620. Thus, the need for door interlock functionality is recognized. 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. These conductors may be covered with suitable shielding for telephone, audio, video or higher-frequency communications circuits. hb``` ea``j~p2nfH 'xXg00,/(_ Iq8PDdg-~ s$!XI;Fn0vu `h`R 1y 0B.":9.@, e`xI;=7O3fvbb8:SC;%O*20] The light switch for the equipment room must be adjacent to the entrance door on the latch side. This strategy works to improve the flexibility of the traveling cable, but it is contrary to a general NEC rule concerning the paralleling of conductors, which is generally done in very large sizes to avoid unwieldy wire pulls and terminations. +1-251-479-4514 | [emailprotected], Trkiye Office The conduit alone can't act as the grounding means. NEC has a further note that the term wheelchair lift has been changed to platform lift.. However, it is likely that for many elevator controllers, this may not be high enough for the available fault current where they will eventually be installed. The elevator pit discharge system is not required to include an oil separator, except as required by section 1003.4. Accordingly, the supply wires are protected only for short circuit, and the overload protection is provided closer to the motor. In elevators provided with Firefighters' Emergency Operation, a drain or sump pump shall be provided. Selective coordination is defined by the NEC as: Localization of an overcurrent condition to restrict outages to the circuit or equipment affected, accomplished by the selection and installation of overcurrent protective devices and their ratings or settings for the full range of available overcurrents, from overload to the maximum available fault current, and for the full range of overcurrent protective device opening times associated with those overcurrents.. It is of great importance that power to the various elevator functions can be quickly and reliably removed from the loads in case of emergency or for maintenance and troubleshooting. To achieve flexibility and endurance, traveling cable is more finely stranded and, where possible, separated into discrete conductors. Such cable groups are to be supported at intervals not over 3 ft. and located so as to be protected from physical damage. 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. (Cross-sectional areas of conductors are given in Chapter 9, Tables 5 through 8. In contrast to the lighting, these receptacles must be connected to GFCI devices. However, this can vary depending on building conditions and exterior grade. Cross-sectional areas of wireways are found by multiplying the two interior dimensions.) So, we see that for elevator work, greater fill is allowed. The sump pump/drain shall have the capacity to remove a minimum of 11.4 m. 3 /h (3,000 gal/h) per elevator. If the equipment must remain energized to perform work, effective insulation and safe electrical working practices should be observed. But the lights don't have to be in the pit itself. 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. Receptacle for pumps located in the pit shall be a single non-GFCI and shall be located 6 inches above the lowest landing. 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 No provision is to be made to automatically restore power. 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. Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page. 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. Where voltages exceed 600, a sign reading DANGER HIGH VOLTAGE is required. Feeders may be installed within the hoistway where the elevator has a driving-machine motor in the hoistway or on the car or counterweight. (g) Stop Switch in Pits. The panel further clarified that the marked SCCR value must be adequate for the available fault current to ensure a safe installation. 1. It need not be exactly centered on the equipment, and working spaces of adjacent pieces of equipment may overlap. Elevator power disconnect (with utility feed marking) located in the machine room or other permitted location. Upon loss of power, the rescuvator controls the cab, lowers it to the designated floor, and opens its doors. 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. Finally, in 1897, the first National Electrical Code (NEC) appeared. 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 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). 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. 0 You are seeing this message for one of three reasons: You have reached your limit of free content. 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. 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. [emailprotected] Requirements for commercial garages per the National Electrical Code. Because they need to move and flex, traveling cables are not required to be in a raceway. U.S. Latham, NY Shopping Miscellaneous Retail Stores, NEC Wheelchair lifts EazyLift Elevators, . This website is using a security service to protect itself from online attacks. 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. We resume with a look at wiring methods, overcurrent protection, grounding and other NEC provisions as they relate to these installations. Besides the initial determination requirement of paragraph (c) (1), the "host" employer must comply with the five (5) requirements of paragraph (c) (8) when engaging another employer (contractor) who will have employees in permit spaces under the control of the host employer. 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. With the new elevator controller requirements, more attention will be focused on the elevator system. 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. While machine room-less designs have been commercially available for many years, their use may still be unknown to some AHJs. 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. APPENDIX A 2.2. 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. To address this issue, Code Making Panel (CMP) 12 of the National Electrical Code acted on several proposed changes to Article 620 during the revision cycle for the 2017 NEC that deal with the proper installation of elevator controllers. Granle is a licensed professional engineer with Sebesta Blomberg & Associates, Rochester, Minn. https://www.facebook.com/ElectricalConstructionMaintenanceMagazine, https://www.linkedin.com/company/electrical-construction-maintenance/, ABCs Construction Backlog Indicator Down to Start 2023, The Most Popular Code Quizzes of the Week from 2021, The 10 Most Popular Photo Galleries of 2021, Whats Wrong Here? This is somewhat broader than A17.1-2007/B44-07. 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. EazyLift Elevators, Stairlifts, Wheelchair Lifts & Ramps. Required lighting shall not be connected to the load side of a ground-fault circuit interrupter. Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. It is further specified the machine-room lighting switch be located at the point of entry. My reasoning comes from 620.24 (A) and (C). Such design innovations require sophisticated wiring strategies. 2. Mobile, AL 36606 USA As stated in Section 7 of the Elevator Industry Field Employees Safety Handbook: Unless it is not feasible, (i.e. 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.