The limit switches are mechanical devices used mainly to limit the movement of various mechanisms that perform primarily reciprocating motions.
The primary applications of the limit and track switches include cranes, hoists, winders, belt conveyors and many others. They are also used as protections against short circuits, locks, etc.
Structurally, they comprise of a lever system mechanically connected to one or more electrical contacts. During the interaction between the lever system and the moving parts of the monitored mechanism, the contacts switch on, which leads to the generation of an electrical signal, which is subsequently used by the control system.