UL 20:2004 pdf download General-Use Snap Switches
Scope
1.1 The requirements of this Standard apply to manually operated, genera-use snap switches forconnection to copper (Cu) or copper-clad conductors used in accordance with the National ElectricaCode(NEC), ANSINFPA 70, or the Canadian Electrical Code (CEC). Part 1, and intended for connectionto wiring systems recognized by the NEC or the CEC, Part 1. ln Canada, requirements for switches forconnection to aluminum (A)) conductors used in accordance with the CEC, Part 1, and intended forconnection to wiring systems recognized by the CEC, Part 1, are covered in Appendix B.
1.2 This Standard applies to ac/dc rated switches for which the load ratings do not exceed 60 A at 250V or less, 30 A at 251 V – 600 V, and 2 hp at 125 V – 600 V or less. This Standard also covers ac-onlyrated switches for which the load ratings do not exceed 30 A at 347 Vac or less.
1.3 This Standard applies to switches constructed to be installed readily in a flush device box or on anoutlet-box cover and intended for connection to branch-circuit wiring.
1.4 This Standard applies to pendant and through-cord switches intended for field installation on flexiblecord and provided with one “on” and one “off” position.
1.5 This Standard applies to switches intended for surface mounting and provided with a separable baseand cover for connection to exposed wiring consisting of nonmetallic sheathed cable or open wiring oninsulators (knob and tube).
1.6 This Standard applies to self-contained switches intended for flush mounting without a separate outletbox and for connection to branch-circuit wiring consisting of one or more non-metallic sheathed cablescontaining copper conductors.
1.7 This Standard applies to ac/dc fixture switches intended to be installed in fixtures to controlincandescent lighting or fans for connection to branch-circuit wiring.
1.8 This Standard also applies to single-pole, momentary-contact door switches constructed to beinstalled readily in a special-purpose device box or on an outlet-box cover for connection to branch-circuitwiring.
1.9 This Standard does not apply to:
a) Clock operated switches specified in the Standard for Clock-Operated Switches, UL 917.and CSA Standard C22.2 No. 177;
b)Dimmer switches specified in the Standard for Solid-State Dimming Controls, UL 1472, andCSA Standard C22.2 No.184.1;
c)Industrial control equipment specified in the Standard for Industria Control Equipment, UL508, and CSA Standard C22.2 No.14;
d) Solid-state, single-phase motor speed controls specified in the Standard for Solid-State FanSpeed Controls,UL 1917, and CSA Standard C22.2 No.156
Special-use and ac-only fixture switches specified in the Standard for Special-Use Switches.eUL 1054, and CSA Standard C22.2 No.55; and
f) Switches for use in hazardous locations specified in the Standard for Switches for Use in Hazardous (Classified) Locations, UL 894, and CSA Standard C22.2 No. 1 59.