These switches are sold in many different formats and styles, which have different advantages and limitations in various applications and device types. Some of the most common variants are:
- On-off
- On-on
- Illuminated rocker
- Round rocker
- Power rocker
- Momentary
- Pushbutton
- Changeover
- Centre-off switch
- On-NONE-Off / On-NONE-On
- E-switch
- Miniature rocker switch (often sold in mm sizings)
- High inrush rocker switches
In the following sections, we will take a look at some of the above styles in more detail.
On-Off
An on-off (or off-on) switch allows the user to select between on and off positions for power delivery to one or more circuits simultaneously. Components sold as on-off rocker switches will typically have just those two positions available although you can also buy on-on versions for more specific applications.
Illuminated
Many rocker switches feature embedded illumination to show whether or not power is being sent to a circuit in a given position. These sorts ofbuilt-in LEDindicators on illuminated rocker switches are especially common in applications like power strips and surge protectors. They are also widely found on dashboard displays, instrument panels and control arrays, as well as in some wall-mounted light switches and appliance breakers.
Momentary
Standard rocker switches latch into whichever position you press them into and remain engaged in that position until you switch them the other way. A momentary switch, however, is only engaged when pushed and returns to a default position when not being pressed. It usually does so with the aid of a built-in spring.
Momentary switches may be called push switches or non-latching switches. They can be designed as either normally on or normally off when in their default positions, although off is far more common. They are widely used on many types of intermittent input devices, from keypad controls to electric door and window mechanisms.
Changeover
A changeover or transfer switch (sometimes written as change over) is typically used to divert Voltage to or from one circuit to another. They are most often used in power supply and mains grid functions, allowing the user to select between one input source - for example, mains power - to a secondary source, such as a backup generator. They can be manual or automated. Some models may effectively function as two simultaneous circuit breakers, flipping in opposite directions in the same instance.
Centre-Off
Another type of rocker switch has a central OFF position. This usually means it will have (at least) two ON positions, typically at either side of the see-sawing mechanism. They may be called on-off-on switches, although centre-off is the preferred terminology, as it is less ambiguous. This type of switch can also be momentary, although in most cases they are designed for fully manual operation in all positions.
