Hand Switch

A hand switch is an electrical switch actuated by a person’s hand motion. These may take the form of toggle, push button, rotary, pull-chain, etc. A common form of industrial push button switch looks something like this:

The threaded neck inserts through a hole cut into a metal or plastic panel, with a matching nut
to hold it in place. Thus, the button faces the human operator(s) while the switch contacts reside
on the other side of the panel.

When pressed, the downward motion of the actuator breaks the electrical bridge between the
two NC contacts, forming a new bridge between the NO contacts:

The schematic diagram symbol for this type of switch looks much like the real thing, with the
normally-closed contact set on top and the normally-open contact set below: