UL 48:2001 pdf download – Electric Signs
UL 48:2001 pdf download – Electric Signs.
24 Switches and Controls
24.1 A switch, a flasher, or a similar device that controls a ballast or transformer shall be rated for the application, or shall have a current rating not less than twice the total current rating of the ballasts or transformers that it controls and a voltage rating of not less than the potential of the circuit In which it Is used.
Exception: An AC general-use snap switch is capable of being used to control ballast and transformer loads not exceeding the current rating of the switch at rated voltage.
24.2 A snap switch used in an outdoor sign shall use no moisture-absorbing materials, such as fiber, in its construction; and water shall not contact the switch or enter the compartment housing the switch when the sign is subjected to the test described in the Exclusion of Water Test. Section 32.
24.3 A device that controls an incandescent lamp shall be rated for the control of tungsten-filament lamps.
Exception No. 1: A snap switch is capable of being used to control a single intermediate, candelabra, or miniature-base lamp, when the switch is rated not less than 6 amperes. 125 volts for a nominal 120-volt circuit or 3 amperes. 250 volts for a nominal 230-volt circuit.
Exception No. 2: An AC general-use snap switch is capable of being used to control a tungsten-filament lamp load not exceeding the ampere rating of the switch at 120 volts.
24.4 A switch for controlling a tungsten-filament lamp load shall have:
a) An L or T rating and a current rating at least equal to that of the tungsten-filament lamp load or
b) An alternating current rating at least six times cx a direct current rating at least ten times that of the tungsten-filament lamp load.
24.5 A switch, relay. or similar device that controls a motor, other than a clock•motor. shall have a horsepower rating not less than that of the motor to be controlled.
Exception: An AC general-use snap switch (not an AC-DC general-use snap switch), is capable of being used to control a motor load not exceeding 80 percent of the ampere rating of the switch at its rated voltage.
24.6 A switch or circuit breaker shall not disconnect the grounded conductor of a circuit.
Exception: The switch or cuwit breaker is not prohibited from disconnecting the grounded conductor of the circuit when it:
a) Simultaneously disconnects each ungrounded conductor or
b) Is arranged so that the grounded conductor cannot be disconnected until each ungrounded conductor has first been disconnected.
24.7 A disconnect switch, when povided. shall disconnect all ungrounded conductors of the supply circuit.
24.8 When provided, an externally-operable disconnect switch shall have a designated off position. When
the switch is operated vertically rather then horizontally, the up position shall be the on position.
25.1 Dedicated type
25.1.1 A sign is capable of being provided with one or mote receptacles each of which is dedicated for the connection of a specific product on or within the sign body, The product intended for connection to the dedicated receptacle shall comply with the appropriate requirements for its product class.
25.1.1 revised hay 2. 2001
25.1.2 The dedicated receptacle shall be of a type that has the same pin configuration as the attachment plug on the dedicated product.
25.1.3 A sign circuit supplying a dedicated receptacle shall have the circuit protected by supplementary overcurrent protection, consisting of a fuse, circuit breaker, or similar devices, having a current rating not exceeding the applicable value specified in Table 25.1. The total load in amperes imposed on the circuit shall not exceed the current rating of the supplementary overcurrent protective device or the values indicated In Table 19.2. See 18.20, 18.21, and 40.1.17.