Marking the elevator controller short-circuit current rating (SCCR) by the elevator controller manufacturer. Depending on your local codes, you can do this by installing heat or smoke detectors within 24 in. Motor controllers are permitted outside the spaces specified above. Weight (passengers, freight, car and attendant machinery) may be fairly substantial, and speed is significant. The basic idea is that there must be a separate, dedicated circuit for car lights, receptacles and ventilation on each car. 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. 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. 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 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. You need to Subscribe to continuing reading. 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. 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. Nevertheless, the primary NEC focus is on elevators, and the intention is to mitigate the hazards associated with the use of electricity. 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. 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. (A) tells us that the lighting and receptacle (s) for the pit must be on separate circuits. GET YOUR CEUS TODAY, 1998-2021. Sign up for our free e-newsletter. Modern electronic elevator controls can be sensitive to temperature shifts. 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. One. 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. 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. 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. 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. 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 511 provides the requirements for commercial garages areas used for the storage or repair of self-propelled vehicles that use combustibles (liquid or gas) for power. Feeders may be installed within the hoistway where the elevator has a driving-machine motor in the hoistway or on the car or counterweight. Dec. 21, 2010. or larger, not exceeding 6 ft. in length, are permitted between control panels and machine motors, machine brakes, motor-generator sets, disconnecting means and pumping motors and valves. 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. Elevator motors are inherently intermittent duty. 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. Additionally, duty on elevator and dumbwaiter motors is rated as intermittent, whereas duty on escalator and moving-walk motors is considered continuous. 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. NEC has a further note that the term wheelchair lift has been changed to platform lift.. 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. 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. Overcurrent devices protecting these branch circuits are to be located in the machine room or similar location. 2.2.2.6 . The code exempts some fairly broad areas where compliance is not expected. 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. 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. 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. Each of these performs a different function, and the wiring mandates vary accordingly. 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. 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 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. NEC Article 620 contains numerous other disconnect provisions, which must be carefully scrutinized prior to design work so the installation is compliant. In addition, the shunt-trip voltage must also be monitored by the Fire Alarm System. Fluid pressure in the cylinder raises and lowers the elevator cab. Similarly, the integrity of the traveling cable is emphasized. If it kills the son of the owner, the son of that builder shall be put to death.. It is important, where mandated, that there be no more than a single disconnecting means, so if emergency action is required, first responders will not be able to power down the equipment from one location. Here again, the lighting is not to be connected to a GFCI, whereas such protection is required for the receptacle(s). Limit switches placed throughout the height of the shaft communicate with the controller and stop the cab at each landing. Mobile, AL 36606 USA 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). 836 Troy Schenectady Road ; Latham, NY 12110 . Because of this, there is often a communications gap between the electrical system designer, whose design typically stops at the required elevator disconnecting means, and the architect who designs the elevator system. 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. For instance, a typical elevator controller may traditionally have SCCR ratings from 5 to 10 kA. 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. Conductors supplying a single power transformer are to have an ampacity not less than the nameplate current rating of the power transformer plus all other connected loads. David Herres NEC Guidelines on Commercial Garages. from components that are not otherwise guarded. 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. f?3-]T2j),l0/%b Even non-composite fiber-optic cable, which does not carry electrical energy, is subject to the code. 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. No provision is to be made to automatically restore power. NEC 620.62 requires the elevator disconnecting means (fused switch or circuit breaker) to selectively coordinate with all supply-side overcurrent devices. The action you just performed triggered the security solution. Car lighting, receptacles and ventilation 2. The feeder OCPD needs to remain closed so the remaining elevators have power and continue to function. 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. 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 demand factor ranges from 1.00 for one elevator on a single feeder to 0.72 for 10 or more elevators on a single feeder. +1-251-479-4514 | [emailprotected], Trkiye Office 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. If the equipment must remain energized to perform work, effective insulation and safe electrical working practices should be observed. It states an elevator is permitted to be run by an emergency or standby power system. For some manufacturers, such as Eaton, testing has been completed to determine the selective coordination ability of current-limiting BussmannTM series fuses with upstream Eaton circuit breakers. Requirements for commercial garages per the National Electrical Code. Performance & security by Cloudflare. 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. . Fuses: Verify that the correct size, type and capacity are installed. Where necessary, it is mandated that suitable guards be provided to protect the cables against damage. You are seeing this message for one of three reasons: You have reached your limit of free content. The two main types of elevators are hydraulic and traction. 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. The conductors must be in their original sheaths or grouped together and taped or corded. 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. A single dedicated receptacle supplying a permanently installed sump pump does not have to be a GFCI type. (B) Lighting Switch. 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. In this case, it may be best if the elevator controller manufacturer does not include the elevator disconnecting means (often offered as a circuit breaker) but instead have the installer provide a separate fused disconnect to comply with NEC 620.51(A) and also achieve a high SCCR for the elevator controller when fuses are provided as specified by the elevator controller and marked on the elevator controller nameplate. However, this can vary depending on building conditions and exterior grade. As such, elevator controller manufacturers should make the effort to rethink their designs to avoid costly system design changes. Additional branch circuits are to supply other utilization equipment not covered above. While machine room-less designs have been commercially available for many years, their use may still be unknown to some AHJs. NEC 70620.85 Smoke detectors to recall elevators on Phase I recall are required to be located on each landing, 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. The sump pump/drain shall have the capacity to remove a minimum of 11.4 m. 3 /h (3,000 gal/h) per elevator. Traditional wiring methods and materials come into play, as always, but it is necessary to rethink their deployment. For this reason, the NEC provides for adequate working space around electrical equipment that may need to be serviced. But by understanding how these items fit together and what purpose they serve, you can have a successful project. Therefore, elevator equipment rooms must maintain a temperature between 50F and 90F. 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. Section 725.45 concerns the location of overcurrent devices and provides for feeder and branch-circuit taps, transformer primary side overcurrent device location and overcurrent device location at the input side of electronic power sources. It is further stipulated that internal voltages of power-conversion equipment and functionally associated equipment, and the operating voltages of wiring interconnecting the equipment, are permitted to be higher, provided that the equipment and wiring are listed for the higher voltages. For example, an inadequately supported ceiling fan could fall and cause injury or property damage. 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). It is further specified the machine-room lighting switch be located at the point of entry. The Code provides guidance through regulations to establish requirements. In elevators provided with Firefighters' Emergency Operation, a drain or sump pump shall be provided. Additionally, ampacities of the individual conductors and flame-retardant properties of the overall cable are important factors. The fan should be on a dedicated circuit. It begins by considering metal and nonmetallic wireways. 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. 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. Beginning with Article 320, Armored Cable (Type AC) and concluding with Article 398, Open Wiring on Insulators, each code-sanctioned cable and raceway is treated, ranging from the familiar Type NM (trade name Romex) to the exotic Integrated Gas Spacer Cable (Type IGS). You must locate this key switch at the main lobby or at the building fire command center. The disconnecting means is also to be a listed device. High-rise buildings pose additional concerns. Every building is different. (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. Moreover, because motors have a higher starting current than other loads, the overcurrent protection protocol is unique to them and somewhat counterintuitive. This may be countered by providing good machine-room ventilation. Liquid-tight flexible nonmetallic conduit, Flexible cords and cables, or conductors grouped together and taped or corded, are permitted without raceway, where they are part of listed equipment, a driving machine or a driving-machine brake, Flexible metal conduit, liquid-tight flexible metal or nonmetallic conduit, 3/8 in. Though I understand how someone might argue two. 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. 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. As stated in Section 7 of the Elevator Industry Field Employees Safety Handbook: Unless it is not feasible, (i.e. Be sure to provide a horn/strobe alarm in large equipment rooms because they can be noisy, isolated places. Notice the definition mentions the full range of operating times. 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. See Section 3 of the. Moreover, it is necessary to consider future worker safety for an indefinite period. 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. 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. The drain or sump pump discharge shall be into the sanitary or storm drainage system through an indirect waste connection. Always verify all conditions and requirements with the state and the AHJ where the installation is taking place. This is something that can be easily accomplished if the elevator controller manufacturer uses components in combination with overcurrent protective devices that are tested and listed with high combination SCCRs. 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.. However, when I've put in elevators, NEC seems to always take a back seat to ANSI, which seems . A second door is required if the equipment is rated over 1200 amps and over 6 ft. wide. Part III, Wiring, looks at the types of wiring that may be installed in hoistways, cars, machine rooms and related spaces. Three wiring categories within hoistways are allowed in addition, each with exceptions. [emailprotected] Building codes were deemed necessary to protect the public against shoddy builders and outmoded construction techniques. This, however, can result in a dramatic increase in cost, space availability (lack thereof), and reduced efficiency. N _rels/.rels ( j0@QN/c[ILj]aGzsFu]U ^[x 1xpf#I)Y*Di")c$qU~31jH[{=E~ 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. GFI Receptacles: GFI receptacles shall be required in all elevator machine rooms, machinery spaces and elevator pit areas. 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. If power is not being supplied to the elevator controller (e.g., open mainline fuses, etc. 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. 2m9 `K]f*F gaR 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. For circuit breakers, time-current curves must be consulted as well as the circuit breaker manufacturers selective coordination tables. 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. The AHJ is saying that this is a violation of 620.23. The usual scenario for electrical injury is shock when electrical current passes through the human body. So, we see that for elevator work, greater fill is allowed. Many people use portable generators until power is restored. The most complex of these is the elevator. 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. You are a subscriber that needs to Sign In. 953 0 obj <> endobj Flexible metal, liquid-tight flexible metal or liquid-tight flexible nonmetallic conduit 3/8 in. A section on branch circuits for car lighting, receptacles, ventilation, heating and air-conditioning contains a number of important provisions. Traction elevators are typically faster and more energy efficient than hydraulic elevators, and are often used for high-rise buildings. 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. 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. Luminaires must be lensed or equipped with wire guards to protect the lamps. 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. Here, the National Electrical Safety Code has jurisdiction. If your specifications require a vent at the top of the shaft for venting smoke, you must provide a key switch with a pilot light to control that vent. Mobile, AL 36606 USA The NEC rule specifies that the minimum size for paralleled conductors is 1/0 AWG, which is much too big for an elevator traveling cable. My reasoning comes from 620.24 (A) and (C). %%EOF 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. Accordingly, the supply wires are protected only for short circuit, and the overload protection is provided closer to the motor. 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. First, you'll need to install lighting in the elevator equipment room (Photo 1) and shaft pit (Photo 2). Elevator cab lights require emergency back-up power. With heavy use on a hot day, the oil can overheat, causing elevator shutdown. As we have seen, a limited number of these are approved for elevator locations car, hoistway, pit and machine room. Corporate Office Freight Elevator Door Control: An Opportunity for Wireless Technology. 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. Your IP: Louisiana State Uniform Construction Code Council adopts the 2014 NEC, Basic three-phase power measurements explained, Safety After the Storm Operating Portable Generators. These may include: The author would like to recognize Jonathan Kennedy for his assistance in creating this article. Many of these are for portable lighting.). It is worth noting that these NEC terms, used throughout Article 620, have been chosen to correlate with A17.1-2007 usage. NEC Article 620 Part IV, Installation of Conductors, contains key mandates for elevator wiring. NEC Article 620 covers elevators, dumbwaiters, escalators, moving walks, platform lifts and stairway chairlifts. The lighting is not to be connected to a GFCI, because the elevator car is not a place that should experience nuisance tripping. 0 Electricity is often one of the initial services to fail during a storm. But, building codes had been in existence for many centuries. 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. Such design innovations require sophisticated wiring strategies. By subscribing, you agree to our User Agreement and Privacy Policy & Cookie Statement. Get more of Elevator World. Below is a summary of these new 2017 NEC sections: In order to comply with these requirements a chain of events must occur. The proposals resulted in adding new requirements in the 2017 NEC for: This article will also discuss other Code requirements that include selective coordination for elevators that are supplied by emergency, legally required standby or critical operation power systems or multiple elevators supplied from a single feeder, and shunt tripping of elevators where the elevator equipment room and/or shaft has a fire suppression sprinkler system. It is stated that traveling cables are to be suspended at the car and hoistway ends, or counterweight end where applicable, so as to reduce the strain on the individual copper conductors to a minimum. It provides that where more than one driving-machine disconnecting means is supplied by a single feeder, the overcurrent protective devices in each disconnecting means are to be selectively coordinated with any other supply side overcurrent protective devices.
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