Resolución 2535: adopta el Código Eléctrico Nacional, versión 1993. (Sustituye el Anejo A del Reglamento 4435)

Exception: Where the attachment plug and cord are located within the vehicle's interior, use of plastic thermoset or elastomer parallel cord Type SPT-3, SP-3, or SPE shall be permitted. (2) If the receptacle provided for connection of the cord to the main circuit is located on the outside of the vehicle, it shall be protected with a ground-fault circuit-interrupter for personnel and be listed for wet locations. A cord located on the outside of a vehicle shall be identified for outdoor use. (3) Unless removable or stored within the vehicle interior, the cord assembly shall have permanent provisions for protection against corrosion and mechanical damage while the vehicle is in transit. (4) The cord shall be installed so as not to permit exposed live attachment plug pins. 70-620 NATIONAL ELECTRICAL CODE (q) Prewiring for Air Conditioning Installation. Prewiring installed for the purpose of facilitating future air-conditioning installation shall conform to the following and other applicable portions of this article. The circuit shall serve no other purpose. (1) An overcurrent-protective device with a rating compatible with the circuit conductors shall be installed in the distribution panelboard and wiring connections completed. (2) The load end of the circuit shall terminate in a junction box with a blank cover or a device listed for the purpose. Where a junction box with a blank cover is used, the free ends of the conductors shall be adequately capped or taped. (3) A label conforming to Section 551-46(d) shall be placed on or adjacent to the junction box and shall read: AIR-CONDITIONING CIRCUIT. THIS CONNECTION IS FOR AIR CONDITIONERS RATED 110-125 VOLT AC, 60 HZ AMPERES MAXIMUM. DO NOT EXCEED CIRCUIT RATING. An ampere rating, not to exceed 80 percent of the circuit rating, shall be legibly marked in the blank space. (r) Prewiring for Generator Installation. Prewiring installed for the purpose of facilitating future generator installation shall conform to the following and other applicable portions of this article. (1) Circuit conductors shall be appropriately sized in relation to the anticipated load and shall be protected by an overcurrent device in accordance with their ampacities. (2) Where junction boxes are utilized at either of the circuit originating or terminus points, free ends of the conductors shall be adequately capped or taped. (3) Where devices such as receptacle outlet, transfer switch, etc., are installed, the installation shall be complete, including circuit conductor connections. All devices shall be listed and appropriately rated. (4) A label conforming to Section 551-46(d) shall be placed on the cover of each junction box containing incomplete circuitry and shall read, as appropriate, either: GENERATOR CIRCUIT. THIS CONNECTION IS FOR GENERATORS RATED 110-125 VOLT AC, 60 HZ AMPERES MAXIMUM. OR GENERATOR CIRCUIT. THIS CONNECTION IS FOR GENERATORS RATED 120/240 VOLT AC, 60 HZ AMPERES MAXIMUM. The correct ampere rating shall be legibly marked in the blank space. 551-48. Conductors and Boxes. (a) Maximum Number of Conductors. The maximum number of conductors permitted in boxes shall be in accordance with Section 370-16. ARTICLE 551 - RECREATIONAL VEHICLES, PARKS 70-621 (b) Free Conductor at Each Box. At least 4 inches (102 mm) of free conductor shall be left at each box except where conductors are intended to loop without joints. 551-49. Grounded Conductors. The identification of grounded conductors shall be in accordance with Section 200-6. 551-50. Connection of Terminals and Splices. Conductor splices and connections at terminals shall be in accordance with Section 110-14. If splices of the equipment grounding conductor in nonmetallic-sheathed cable are made in boxes containing devices, the splices shall be insulated. 551-51. Switches. Switches shall be rated as follows: (a) Lighting Circuits. For lighting circuits, switches shall be rated not less than 10 amperes, 120-125 volts and in no case less than the connected load. (b) Motors or Other Loads. For motors or other loads, switches shall have ampere or horsepower ratings, or both, adequate for loads controlled. (An ac general-use snap switch shall be permitted to control a motor 2 horsepower or less with full-load current not over 80 percent of the switch ampere rating.) 551-52. Receptacles. All receptacle outlets shall be (1) of the grounding type and (2) installed in accordance with Sections 210-7 and 210-21. 551-53. Lighting Fixtures. (a) General. Any combustible wall or ceiling finish exposed between the edge of a fixture canopy, or pan and the outlet box, shall be covered with noncombustible material or a material identified for the purpose. (b) Shower Fixtures. If a lighting fixture is provided over a bathtub or in a shower stall, it shall be of the enclosed and gasketed type and listed for the type of installation, and it shall be ground-fault circuit-interrupter protected if rated at 120 volts, nominal. The switch for shower lighting fixtures and exhaust fans, located over a tub or in a shower stall, shall be located outside the tub or shower space. (c) Outdoor Outlets, Fixtures, Air-Cooling Equipment, Etc. Outdoor fixtures and other equipment shall be listed for outdoor use. 551-54. Grounding. (See also Section 551-56 on bonding of noncurrentcarrying metal parts.) (a) Power-Supply Grounding. The grounding conductor in the supply cord or feeder shall be connected to the grounding bus or other approved grounding means in the distribution panelboard. (b) Distribution Panelboard. The distribution panelboard shall have a grounding bus with sufficient terminals for all grounding conductors or other approved grounding means. (c) Insulated Neutral. (1) The grounded circuit conductor (neutral) shall be insulated from the equipment grounding conductors and from equipment enclosures and 70-622 NATIONAL ELECTRICAL CODE other grounded parts. The grounded (neutral) circuit terminals in the distribution panelboard and in ranges, clothes dryers, counter-mounted cooking units, and wall-mounted ovens shall be insulated from the equipment enclosure. Bonding screws, straps, or buses in the distribution panelboard or in appliances shall be removed and discarded. (2) Connection of electric ranges and electric clothes dryers utilizing a grounded (neutral) conductor, if cord-connected, shall be made with 4-conductor cord and 3-pole, 4-wire, grounding-type plug caps and receptacles. 551-55. Interior Equipment Grounding. (a) Exposed Metal Parts. In the electrical system, all exposed metal parts, enclosures, frames, lighting fixture canopies, etc., shall be effectively bonded to the grounding terminals or enclosure of the distribution panelboard. (b) Equipment Grounding Conductors. Bare wires, green-colored wires, or green wires with yellow stripe(s) shall be used for equipment grounding conductors only. (c) Grounding of Electrical Equipment. Where grounding of electrical equipment is specified, it shall be permitted as follows: (1) Connection of metal raceway (conduit or electrical metallic tubing), the sheath of Type MC and Type MI cable where the sheath is identified for grounding, or the armor of Type AC cable to metal enclosures. (2) A connection between the one or more equipment grounding conductors and a metal box by means of a grounding screw, which shall be used for no other purpose, or a listed grounding device. (3) The equipment grounding conductor in nonmetallic-sheathed cable shall be permitted to be secured under a screw threaded into the fixture canopy other than a mounting screw or cover screw, or attached to a listed grounding means (plate) in a nonmetallic outlet box for fixture mounting (grounding means shall also be permitted for fixture attachment screws). (d) Grounding Connection in Nonmetallic Box. A connection between the one or more grounding conductors brought into a nonmetallic outlet box shall be so arranged that a connection can be made to any fitting or device in that box that requires grounding. (e) Grounding Continuity. Where more than one equipment grounding conductor of a branch circuit enters a box, all such conductors shall be in good electrical contact with each other, and the arrangement shall be such that the disconnection or removal of a receptacle, fixture, or other device fed from the box will not interfere with or interrupt the grounding continuity. (f) Cord-Connected Appliances. Cord-connected appliances, such as washing machines, clothes dryers, refrigerators, and the electrical system of gas ranges, etc., shall be grounded by means of an approved cord with equipment grounding conductor and grounding-type attachment plug. 551-56. Bonding of Noncurrent-Carrying Metal Parts. (a) Required Bonding. All exposed noncurrent-carrying metal parts that may become energized shall be effectively bonded to the grounding terminal or enclosure of the distribution panelboard. ARTICLE 551 - RECREATIONAL VEHICLES, PARKS 70-623 (b) Bonding Chassis. A bonding conductor shall be connected between any distribution panelboard and an accessible terminal on the chassis. Aluminum or copper-clad aluminum conductors shall not be used for bonding if such conductors or their terminals are exposed to corrosive elements. Exception: Any recreational vehicle that employs a unitized metal chassis-frame construction to which the distribution panelboard is securely fastened with a bolt(s) and nut(s) or by welding or riveting shall be considered to be bonded. (c) Bonding Conductor Requirements. Grounding terminals shall be of the solderless type and listed as pressure terminal connectors recognized for the wire size used. The bonding conductor shall be solid or stranded, insulated or bare, and shall be No. 8 copper minimum, or equal. (d) Metallic Roof and Exterior Bonding. The metal roof and exterior covering shall be considered bonded where: (1) The metal panels overlap one another and are securely attached to the wood or metal frame parts by metal fasteners, and (2) The lower panel of the metal exterior covering is secured by metal fasteners at each cross member of the chassis, or the lower panel is bonded to the chassis by a metal strap. (e) Gas, Water, and Waste Pipe Bonding. The gas, water, and waste pipes shall be considered grounded if they are bonded to the chassis. (FPN): See Section 551-56(b) for chassis bonding. (f) Furnace and Metal Air Duct Bonding. Furnace and metal circulating air ducts shall be bonded. 551-57. Appliance Accessibility and Fastening. Every appliance shall be accessible for inspection, service, repair, and replacement without removal of permanent construction. Means shall be provided to securely fasten appliances in place when the recreational vehicle is in transit. F. Factory Tests 551-60. Factory Tests (Electrical). Each recreational vehicle shall be subjected to the following tests: (a) Circuits of 120 Volts or 120/240 Volts. Each recreational vehicle designed with a 120-volt or a 120/240-volt electrical system shall withstand the applied potential without electrical breakdown of a 1-minute, 900-volt dielectric strength test, or a 1-second, 1080-volt dielectric strength test, with all switches closed, between ungrounded and grounded conductors I and the recreational vehicle ground. During the test, all switches and other controls shall be in the "on" position. Fixtures and permanently installed appliances shall not be required to withstand this test. Each recreational vehicle shall be subjected to (1) a continuity test to I assure that all metal parts are properly bonded; (2) operational tests to demonstrate that all equipment is properly connected and in working order; and (3) polarity checks to determine that connections have been properly made. 70-624 NATIONAL ELECTRICAL CODE (b) Low-Voltage Circuits. Low-voltage circuit conductors in each recreational vehicle shall withstand the applied potential without electrical breakdown of a 1-minute, 500-volt or a 1-second, 600-volt dielectric strength test. The potential shall be applied between ungrounded and grounded conductors. The test shall be permitted on running light circuits before the lights are installed provided the vehicle's outer covering and interior cabinetry has been secured. The braking circuit shall be permitted to be tested before being connected to the brakes, provided the wiring has been completely secured. G. Recreational Vehicle Parks 551-71. Type Receptacles Provided. Every recreational vehicle site with electrical supply shall be equipped with at least one 20-ampere, 125-volt receptacle. A minimum of 75 percent of all recreational vehicle sites with electrical supply shall each be equipped with a 30-ampere, 125-volt receptacle conforming to Figure 551-46(c). This supply shall be permitted to include additional receptacle configurations conforming to Section 551-81. The remainder of all recreational vehicle sites with electrical supply shall be equipped with one or more of the receptacle configurations conforming to Section 551-81. All 20-ampere, 125-volt receptacles shall have listed ground-fault circuit-interrupter protection for personnel. Additional receptacles shall be permitted for the connection of electrical equipment outside the recreational vehicle within the recreational vehicle park. All such 125-volt, single-phase, 15- and 20-ampere receptacles shall have ground-fault circuit-interrupter protection for personnel. 551-72. Distribution System. The recreational vehicle park secondary electrical distribution system to recreational vehicle sites shall be derived from a single-phase 120/240-volt, 3-wire system. (FPN): On a 120/240-volt, 3-wire, single-phase service or feeder, the neutral cannot be reduced in size (below the size of the ungrounded conductors) if there are no 240-volt loads, because, under the most severe conditions of unbalance, the neutral will carry the same current as the ungrounded conductor supplying the load. 551-73. Calculated Load. (a) Basis of Calculations. Electrical service and feeders shall be calculated on the basis of not less than 9,600 volt-amperes per site equipped with 50-ampere 120/240-volt supply facilities, 3,600 volt-amperes per site equipped with both 20-ampere and 30-ampere supply facilities, and 2,400 volt-amperes per site equipped with only 20-ampere supply facilities. The demand factors set forth in Table 551-73 shall be the minimum allowable demand factors that shall be permitted in calculating load for service and feeders. Loads for other amenities such as, but not limited to, service buildings, recreational buildings, and swimming pools shall be sized separately and then be added to the value calculated for the recreational vehicle sites where they are all supplied by one service. ARTICLE 551 - RECREATIONAL VEHICLES, PARKS 70-625 Table 551-73. Demand Factors for Site Feeders and Service-Entrance Conductors for Park Sites Number of Demand Number of Demand Recreational Vehicle Factor Recreational Vehicle Factor Sites (percent) Sites (percent) 1 100 10-12 50 2 90 13-15 48 3 80 16-18 47 4 75 19-21 45 5 65 22-24 43 6 60 25-35 42 7-9 55 36 plus 41 (b) Transformers and Secondary Distribution Panelboards. For the purpose of this Code, where the park service exceeds 240 volts, transformers and secondary distribution panelboards shall be treated as services. (c) Demand Factors. The demand factor for a given number of sites shall apply to all sites indicated. For example: twenty sites calculated at 42 percent of 3,600 volt-amperes result in a permissible demand of 1512 voltamperes per site or a total of 30,240 volt-amperes for twenty sites. (FPN): These demand factors may be inadequate in areas of extreme hot or cold temperature with loaded circuits for heating or air conditioning. (d) Feeder Circuit Capacity. Recreational vehicle site feeder circuit conductors shall have adequate ampacity for the loads supplied and shall be rated at not less than 30 amperes. The grounded conductors shall have the same ampacity as the ungrounded conductors. (FPN): Due to the long circuit lengths typical in most recreational vehicle parks, feeder conductor sizes found in ampacity tables of Article 310 may be inadequate to maintain the voltage regulation suggested in the Fine Print Note to Section 210-19. Total circuit voltage drop is a summation of the voltage drops of each serial circuit segment, where the load for each segment is calculated using the load that segment sees and the demand factors of Section 551-73(a). 551-74. Overcurrent Protection. Overcurrent protection shall be provided in accordance with Article 240. 551-75. Grounding. All electrical equipment and installations in recreational vehicle parks shall be grounded as required by Article 250. 551-76. Recreational Vehicle Site Supply Equipment. (a) Location. Where provided, the recreational vehicle site electrical supply equipment shall be located on the left (road) side of the parked vehicle, on a line that is 9 feet (2.74 m), ± 1 foot (0.3 m), from the longitudinal centerline of the stand and shall be located at any point on this line from the rear of the stand to 15 feet (4.57 m) forward of the rear of the stand. 70-626 NATIONAL ELECTRICAL CODE Exception: For pull-through sites, it shall be permitted to locate the electrical supply equipment at any point along the line from 16 feet (4.88 m) forward of the rear of the stand to 32 feet (9.75 m) forward of the rear of the stand. (b) Disconnecting Means. A disconnecting switch or circuit breaker shall be provided in the site supply equipment for disconnecting the power supply to the recreational vehicle. (c) Access. All site supply equipment shall be accessible by an unobstructed entrance or passageway not less than 2 feet (610 mm) wide and 6½ feet (1.98 m) high. (d) Mounting Height. Site supply equipment shall be located not less than 2 feet (610 mm) nor more than 6½ feet (1.98 m) above the ground. (e) Working Space. Sufficient space shall be provided and maintained about all electric equipment to permit ready and safe operation, in accordance with Section 110-16. 551-77. Grounding, Recreational Vehicle Site Supply Equipment. (a) Exposed Noncurrent-Carrying Metal Parts. Exposed noncurrentcarrying metal parts of fixed equipment, metal boxes, cabinets, and fittings, that are not electrically connected to grounded equipment, shall be grounded by a continuous equipment grounding conductor run with the circuit conductors from the service equipment or from the transformer of a secondary distribution system. Equipment grounding conductors shall be sized in accordance with Section 250-95. The arrangement of equipment grounding connections shall be such that the disconnection or removal of a receptacle or other device will not interfere with, or interrupt, the grounding continuity. (b) Secondary Distribution System. Each secondary distribution system shall be grounded at the transformer. (c) Neutral Conductor Not to Be Used as an Equipment Ground. The neutral conductor shall not be used as an equipment ground for recreational vehicles or equipment within the recreational vehicle park. (d) No Connection on the Load Side. No connection to a grounding electrode shall be made to the neutral conductor on the load side of the service disconnecting means or tranformer distribution panelboard. 551-78. Protection of Outdoor Equipment. (a) Wet Locations. All switches, circuit breakers, receptacles, control equipment, and metering devices located in wet locations or outside of a building shall be rainproof equipment. (b) Meters. If secondary meters are installed, meter sockets without meters installed shall be blanked-off with an approved blanking plate. 551-79. Clearance for Overhead Conductors. Open conductors of not over 600 volts, nominal, shall have a vertical clearance of not less than 18 feet (5.49 m) and a horizontal clearance of not less than 3 feet (914 mm) in all areas subject to recreational vehicle movement. In all other areas, clearances shall conform to Sections 225-18 and 225-19.