Figure 3-11.Two- and three-position switches.
Momentary and Locked Position Switches
In some switches, one or more of the switch positions are MOMENTARY. This means that the
switch will only remain in the momentary position as long as the actuator is held in that position. As soon
as you let go of the actuator, the switch will return to a non-momentary position. The starter switch on an
automobile is an example of a momentary switch. As soon as you release the switch, it no longer applies
power to the starter.
Another type of switch can be LOCKED IN or OUT of some of the switch positions. This locking
prevents the accidental movement of the switch. If a switch has locked-in positions, the switch cannot be
moved from those positions accidentally (by the switch being bumped or mistaken for an unlocked
switch). If the switch has locked-out positions, the switch cannot be moved into those positions
accidentally. Figure 3-12 shows a three-position, locking switch.