PGSLOT08 RTP SLOT This page was last edited on 5 February 2024, at 06:23 (UTC). This page was last edited on 26 April 2022, at 05:55 (UTC). However, many switches indicate their status by purely mechanical means, such as by the position of a toggle handle, or the visibility of a brightly painted indicator flap. These switches appear externally similar to single pole, single throw (SPST) switches, but have extra connections which allow a circuit to be controlled from multiple locations. It is not unusual to see century-old light switches still in functional use. An optional master control can be added that turns all lights in the facility on or off simultaneously under the control of a timer or computer. Movement of the switch control lever applies tension to a spring until a tipping point is reached, and the contacts suddenly snap open or closed as the spring tension is released. When a switch is designed to switch significant power, the transitional state of the switch as well as the ability to withstand continuous operating currents must be considered.|Paul s. Walsh