ACCUPROBE INC.

Probe card edge sensors provide z axis position information to test applications. Accuprobe can supply a wide range of edge sensors based on z-adjustable or blade type probes. Standard and isolated versions are also available.  

Typically, the switch is a normally closed contact which indicates, when opened, that the test probes are in contact with the test pads.  The switch is where the action is in the edge sensor and the switch configuration defines the applications.