Midway Start Button (what contact is what?)

[CWorley]

The contacts are labeled A, B, and C.  Which one is which?

Thanks!

[dendawg]

The contacts on a typical arcade push button microswitch are usually:

Ground/Common
Nomally Open (pressing the button closes the circuit)
Normally Closed (pressing the button opens the circuit)

Typically Ground and Normally Open are the only contacts you should need.

Testing continuity with a multimeter should help you determine which is which.

[Unstupid]

A- Normally Open
B- Normally Closed
C- Ground/Common

A multimeter can be your best friend! 

[CWorley]

Thanks guys!