Xerox Paser 7400 Service Manual page 58

Microswitches
Microswitches are used primarily as paper size sensors and cover interlocks. They are
in a normally open state, and close when actuated. A bank of microswitches detect
paper size in the universal trays. Microswitches also employ hooks or catches for
retention in the bracket or frame.
s7400-311
2-26 Phaser 7400 Color Printer Options Service Manual