Later in the 19th century, Thomas Edison and his associates built an electrical distribution system in Lower Manhattan. If you specify a rescuvator, you must also specify a disconnect switch with an auxiliary contact that opens when the disconnect arm moves to the open position, but stays closed when the OCPD trips. 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). To avoid this situation, designers can specify elevator controls with a safety feature commonly called a rescuvator. !>x=yy Bvv8?~e PK ! Your elevator supplier will take care of all the wiring and related code requirements for the elevator cab and the various controls. (f) Illumination of Pits. 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. These may include: The author would like to recognize Jonathan Kennedy for his assistance in creating this article. Depending on your local codes, you can do this by installing heat or smoke detectors within 24 in. We generally think of the 19th century as the great age of building codes. An example would be the elevator, as well as all wiring in a utility-owned administration building. Hard-service cords are permitted only as flexible connections for the top-of-car operating device or the car-top work light. All Rights Reserved | Contact Us | Privacy Policy. 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 all cases, the working space must permit at least a 90 opening of equipment doors or hinged panels. A raceway that comes loose on the inside of a hoistway could catch on a moving car, causing immense damage and hazard to users. The two main types of elevators are hydraulic and traction. These are covered for generic, non-elevator specific use in earlier articles, 376 and 378, in Chapter 3, Wiring Methods and Materials. The Uniform Building Code requires two-way communications between the central command center and the elevators, each elevator lobby, emergency power rooms, and by entries into enclosed stairways (Section 403.5.3). 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 usual scenario for electrical injury is shock when electrical current passes through the human body. Based on the analysis, the arc-flash boundaries at the elevator/escalator controllers ranged from 3-16 in. 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. The code notes that elevator rails or other hoistway equipment are not to be used as the grounding conductor for lightning-protection systems. As always, the best advice in all instancesdo your homework, communicate often, and document decisions made. 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. The drain or sump pump discharge shall be into the sanitary or storm drainage system through an indirect waste connection. It states an elevator is permitted to be run by an emergency or standby power system. In driving through commercialized suburban areas, you frequently see paralleled conductors for large retail grocers (where there is a heavy refrigeration load). If you can illuminate the pit using lights that are "above the top of the pit" (whatever that . Many of these are for portable lighting.). 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. above the pit floor, shall: Be weatherproof (NEMA 4). NEC Article 620 covers elevators, dumbwaiters, escalators, moving walks, platform lifts and stairway chairlifts. A second door is required if the equipment is rated over 1200 amps and over 6 ft. wide. Elevator cab lights require emergency back-up power. It begins by considering metal and nonmetallic wireways. Something went wrong. 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)]. Accordingly, the supply wires are protected only for short circuit, and the overload protection is provided closer to the motor. For just $7.99 per month, you can gain access to more than 5,000 articles from all Elevator World Publications, this includes EW Global, EW Europe, EW India, EW Middle East, EW Turkey, and EW UK. In an elevator machine room, where space may be limited in the first place, the working-space mandate must be factored in very early in the design process lest an unthinkable amount of rework be necessary. ), 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. See Section 3 of the. 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. (C) Duplex Receptacle. 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. Corporate Office Hazards created by water, snow or condensation in the work area can cause slips, falls and accidental contact. 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. 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. But the lights don't have to be in the pit itself. 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. Related Code Sections 802.1.8 Indirect/Special Waste, Elevator Pit Drain or Sump Pump Requirements for commercial garages per the National Electrical Code. 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. 1993 NEC 15-20 Amp 120 volt Receptacle Requirements: Wet bar sinks, all bathrooms, roof tops, elevator machines rooms, elevator car tops, elevator pits. 836 Troy Schenectady Road Latham, NY 12110 . C.1.4 ELEVATOR PIT REQUIREMENTS 1. 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. 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. For elevators that regenerate power back into a power source unable to absorb the regenerative power under overhauling elevator load conditions, a means to absorb this power is to be provided. +91 8025357028, 2022 Elevator World, LLC. For platform lifts and stairway chairlifts, the duty is intermittent. NEC Article 620 Part VI, Disconnecting Means and Control, is rather exacting. 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. 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. These are the principle NEC 2011 Article 620 mandates. 3. Moreover, it is necessary to consider future worker safety for an indefinite period. 0 However, this can vary depending on building conditions and exterior grade. The lighting switch shall be located so as to be readily accessible from the pit access door. These 29 CFR 1910.146 (c) (8) requirements are: 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. So, we see that for elevator work, greater fill is allowed. The Code provides guidance through regulations to establish requirements. 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. NFPA 72 requires the control circuit between the Fire Alarm System and the shunt trip be monitored for integrity. 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. Part VII, Overcurrent Protection, divides this topic into four categories for elevators and similar equipment, depending upon the nature of the specific equipment: For operating devices and control and signaling circuits, protection against overcurrent is in accordance with the requirements of Sections 725.43 and 725.45. For all of this to come together in the real world, there had to be some assurance that these new technologies could be used safely on a wide scale. The same figure applies to nonmetallic wireways. Hard-service cords and junior hard-service cords are permitted as flexible connections between the fixed wiring on the car and devices on the car doors or gates. from the exposed components, and the incident energy calculated at 18 in. This is especially true in an elevator shaft where measures have to be taken to ensure that a hazardous situation is not created. The floor specified as the designated landing, which must be approved by the Fire Marshal, is usually the floor on grade level so passengers can quickly exit to the outside. For just $7.99 per month, you can gain access to more than 5,000 articles from all Elevator World Publications, this includes EW Global, EW Europe, EW India, EW Middle East, EW Turkey, and EW UK. Car air-conditioning and heating units 3. 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. Always verify all conditions and requirements with the state and the AHJ where the installation is taking place. 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. 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. 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. If the equipment must remain energized to perform work, effective insulation and safe electrical working practices should be observed. NEC 2011 also addresses branch circuits for machine room or control room/machinery space or control-space lighting and receptacles. Many people use portable generators until power is restored. U.S. Latham, NY Shopping Miscellaneous Retail Stores, NEC Wheelchair lifts EazyLift Elevators, . The main concern is to ensure that workers may escape to safety in the awful circumstance of an arc-fault event. h-`7 The fire loading resulting from an accumulation of abandoned low-voltage cabling may be considerable, and has to be understood and dealt with. Elevator power disconnect (with utility feed marking) located in the machine room or other permitted location. 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. N _rels/.rels ( j0@QN/c[ILj]aGzsFu]U ^[x 1xpf#I)Y*Di")c$qU~31jH[{=E~ 974 0 obj <>/Filter/FlateDecode/ID[<64E135C225F1064D91BC8119D14516A9>]/Index[953 36]/Info 952 0 R/Length 105/Prev 204101/Root 954 0 R/Size 989/Type/XRef/W[1 3 1]>>stream -inch conduit is needed to the sump pump. NEC Article 0: Elevator art by David Herres Continued. 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. Feeders may be installed within the hoistway where the elevator has a driving-machine motor in the hoistway or on the car or counterweight. Such vehicles include, but are not . endstream endobj startxref The basic wiring methods are rigid-metal, rigid nonmetallic or intermediate-metal conduit; electrical metallic or rigid nonmetallic tubing; wireways; or Type MC, MI or AC cable, unless otherwise permitted. 68 | WWW.ELEVATORWORLD.COM | June 2012 Continuing Education . Since 1953, Elevator World, Inc. has been the premier publisher for the global vertical transportation industry. Machine room-less elevator installations incorporate the elevator controller and often the primary disconnecting means in a convenient package that is located within the elevator shaft. As they review the plans and the construction site, they may have conflicting interpretations or requirements. It is important for design engineers to communicate this with the architect and owner during the design phase, as it will impact space needs elsewhere in the facility to accommodate electrical equipment. It employs specialists in Mobile, Alabama, and has technical and news correspondents around the world. 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). The thinking behind this requirement is that the injured worker could have severe hand burns and be unable to operate a conventional doorknob. 23.254.250.15 The conduit alone can't act as the grounding means. By subscribing, you agree to our User Agreement and Privacy Policy & Cookie Statement. Section 620.62, Selective Coordination, is central to multi-elevator installations and must be closely observed. Corporate Office But by understanding how these items fit together and what purpose they serve, you can have a successful project. ), advise the building owner to correct the condition. All rights reserved. Society of Mechanical Engineers. The AHJ is saying that this is a violation of 620.23. 4.0 (2 Reviews) (2) CLAIMED . The electrical system designer needs to communicate this information to the person responsible for specifying the elevator controller, which is most often the architect. There are options available to achieve this depending upon the customers needs. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. And so the needs can be very different. This is not the elevator companys responsibility. For circuit breakers, time-current curves must be consulted as well as the circuit breaker manufacturers selective coordination tables. Other requirements: Spa's and Hot Tubs 1996 NEC 15-20 Amp 120 volt Receptacle Requirements for Dwelling units: All outdoor It is of great importance for the design engineer to communicate with their local authority having jurisdiction (AHJ) to determine fire alarm requirements for the respective elevator installation. 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. Additional requirements concern escape routes. The pump sends hydraulic fluid from the reservoir to the cylinder, buried deep below the elevator shaft. Mobile, AL 36606 USA APPENDIX A 2.2. This is because the material may contribute fuel to a fire that has originated elsewhere. Shi Liguang, Yao Lianghong, Luo Zhiqun and Wan Jianru, Constructional Stretch and Hoist-Rope Tension . Marking the elevator controller short-circuit current rating (SCCR) by the elevator controller manufacturer. The traveling cable or raceway is also permitted to include shielded conductors and/or one or more coaxial cables.