UL 48:2011 pdf download – Electric Signs. Field-wiring terminals
4, A pressure wire type terminal or a wire binding screw shall be of the type suitable for held wiring. A terminal intended for connection of a grounded conductor of an ac supply shall be metal substantially white or silver in color or be marked adjacent to the terminal with the words NEUTRAL. N, W or ‘White”. No other terminal shall be substantially white or silver in color. A terminal intended for connection of a dc supply shall be marked with the symbols ‘— arid on or immediately adjacent to the supply terminals. The lettering and symbols shall be minimum
6.4-mm (0.025-in) high. Ink, paint, die stamping and other similar marking means are not prohibited from being used as the marking method. Separation of circuits Wiring operating at different potentials shall comply with one or more of the following conditions:
a) Wiring of different circuits and potential mechanically secured and routed to comply with the minimum spacing requirements in Tables 4.6 or 4.7;
b) Wiring of different circuits and potentials provided with a grounded metal barrier minimum 0.4-mm (0.016-in) thick, or other enclosure rated materials, between the Iwo current carrying parts, with each part secured in a manner that maintains them on opposite sides of the barrier. The barrier shall have no openings; or
C) Wiring of each circuit Is provided with insulation rated for the highest voltage of all circuits. Strain relief
4.2,5.4,1 Strain-relief shall be provided when a pull exerted on external wiring or cord would transmit to a splice, displace an internal corronent. or reduce spacings The construction shall comply with the Strain-Relief Test, 5.4. A strain-relief is not required when the conductors of the supply cord are assembled to a wiring device, such as a switch, a lampholder, or similar component, by the manufacturer of the wiring device such that the replacement of the cord requires the disassembly of the wiring device through the use of non-ordinary tools. In cord-connected signs, internal and external wiring accessible during user servicing shall be provided with strain-relief such that strain is not transmitted to connections when tested in accordance with the Strain-relief Test. 5.4. A strain-refief is not required to be provided when the conductor is integral to a ballast. lampholder, or a similar component that complies with the applicable requirements for the component, and the component is required to have strain-relief, Splices and connections,1 A splice shall be mechanically secured and shall provide reliable electrical contact. It shall be soldered unless a splicing device rated or constructed for the intended purpose is used. A soldered joint and a splice made with an uninsulated wire connector shall be covered with
minimum 3 turns of electrical insulating tape that complies with the Standard for Polyvinyl Chloride,
Polyethylene, and Rubher Insulating Tape, UL 510, insulating tubing that complies with the Standard for
Extruded Insulating Tubing, UL 224, or insulating sleeving that complies with the Standard for Coated
Electrical Sleeving. UL 1441. The voltage rating of an insulated wire connector shall not be less than the voltage of the circuit in which the connector is used. A wire connector shall be used to join a combination consisting only of the sizes and numbers of wires for which it is rated. Mechanical security and protection
4, Wiring shall be run and fastened reliably so as to be mechanically secure.
4, Wiring shall be protected or permanently positioned away from sharp edges and points, burrs, moving parts, and similar places where the insulation on conductors might be abraded or otherwise damaged during shipment, installation or use. Wiring shall be protected or permanently positioned away from the threads and points of sell-tapping screws, thread-cutting screws, self-drilling thread-cutting screws, thread-forming screws, or other screws with sharp edges and/or points, and machine screws of 0.48 cm (3116 in) or smaller diameter. Secondary circuits (over 1000 V) General A current carrying part located in a secondary circuit operating above 1000 Vac mis shall comply with enclosure, accessibility, and electrical requirements in this standard. No spacings are required between the GTO cable and the metal conduit/tubing it is routed in. Glass tubing that functions as an enclosure, an accessible barrier or a water shield shall.