Selector Switch

A simple switch just closes or opens an electrical circuit (in other words, turns it on or off).

A selector switch can also be as simple as that, or can offer more options. The most common example might be a "Hand-Off-Auto" (3-position) switch. The "Hand" position will typically bypass various controllers and feed the controlled item directly. The "Off" position interrupts power to the controlled item. The "Auto" position sends power through a further device such as a pressure/flow/temperature switch that then cycles the controlled item automatically.

There are many variations to this basic idea. The more complex ones may be called "cam switches" or "drum switches." They can turn or off virtually any combination of controlled devices.

When a selector switch is moved to a position, it maintains that state until moved again. In contrast, a push-button opens or closes a contact momentarily.

as the name itself suggests it a switch for selecting mode of operation......it can be hand mode or auto mode or zero(off) mode( 3 way ss)........2 way SS (ON-0FF)...4 way SS, 6 way SS etc......they r used in switchgears, automation , synchronisation,etc..most electrical installation..........