Current through Register Vol. 54, No. 49, December 7, 2024
Section 139.74 - Temporary wiring(a) Feeders must be provided with overcurrent protection in accordance with the load imposed and conductor size as specified in Article 240 of the National Electrical Code.(b) Branch circuits must originate in an approved power outlet or panelboard. Conductors shall be permitted within multiconductors. Conductors shall be protected by overcurrent devices at their rated capacity.(c) Receptacles must be of the grounding type. Unless installed in a complete metallic raceway, branch circuits must contain a separate equipment grounding conductor and all receptacles must be electrically connected to the grounding conductor.(d) Bare conductors or earth returns may not be used for the wiring of a temporary circuit.(e) Suitable disconnecting switches or plug connectors shall be installed to permit the disconnection of ungrounded conductors of a temporary circuit.(f) Lamps for general illumination exclusive of decorative or festoon lighting shall be protected from accidental contact or breakage. Protection shall be provided by elevation of at least 7 feet from a normal working surface or by a suitable fixture or lamp-holder with a guard.(g) Temporary wiring over 600 volts shall be permitted during periods of construction, tests, experiment or emergency. A less permanent class of wiring and equipment shall be permitted than would be required for permanent installations.(h) Suitable fencing, barriers or other effective means shall be provided to prevent access of other than authorized and qualified personnel to temporary wiring over 600 volts.(i) Temporary wiring over 600 volts shall be removed immediately upon completion of construction or purpose for which the wiring was installed.(j) Temporary electric wiring, if suspended, shall be supported so that its protective insulation will not be damaged.(k) Overcurrent protection devices may not be installed in neutral or grounding conductors.(l) Where electrical power is supplied for an amusement ride by a generating system, the generator and equipment must be properly grounded.(m) Receptacles and attachment plugs must be of the grounding type and have ground fault interrupter (GFI) protection.(n) Electrical installations and each electrically powered amusement ride must be effective as to noncurrent carrying metal parts which may become energized and which are exposed to contact by personnel. The path to ground from circuits, equipment and conductor enclosures must:(1) Be permanent and continuous.(2) Have ample carrying capacity to conduct currents liable to be imposed on it.(3) Have impedance, as evidenced by testing, sufficiently low to limit the potential above ground and to facilitate the operation of the overcurrent devices in the circuit.(o) Grounding which does not have a resistance to ground of 25 ohms or less as evidenced by testing shall be augmented by additional electrodes as needed spaced not less than 6 feet apart.(p) Temporary electrical lines placed at ground level must be of the "S" or equivalent type and be adequately insulated and protected in areas of vehicular or pedestrian traffic to provide the maximum public safety.The provisions of this § 139.74 amended December 12, 2008, effective 12/13/2008, 38 Pa.B. 6843.