Types of Electrical Switches Used in Everyday Life

Electrical switches are used every day in order to control electronics and electrical devices. Switches allow us to submit input as to how those devices function, often to turn them on and off.

Electricity needs a closed loop in order to flow. When the loop is broken or opened, the electricity stops flowing.

Switches are often used to turn devices on and off, but they can also be used to send signals.

There are many uses for switches, therefore there’s a wide variety of switches with different properties.

Types of Electrical Switches

Normally open vs normally closed switches.

A normally open switch also known as NO switch, is a switch that is off until you turn it on.

Can be found in: automotive fuel injectors, fire sprinkler systems, burglar alarm systems, some computer keyboards, conveyor belts, automatic doors, emergency stop buttons and fire alarm release buttons.

A normally closed switch is on when you push it, and remains on even if you stop pushing.
To move the switch off, you have to push it again.

Can be found in: safety devices, in devices controlling the movement of a machine or process, to monitor and control the flow of materials or liquids, to regulate the temperature of a process, etc.

A switch can be momentary or maintained.

A momentary switch makes or breaks a connection when actuated, but once the user lets go, it will return to its default state. This type of switch is commonly found in video games, or in the keyboard of your computer. These buttons can be push buttons, they can be toggle switches or often joysticks used in game controllers.

A maintained switch is called this way because will maintain its state until it’s actuated into a new one. When switched on, it will stay there until it is switched to off, and will remain in the ‘off’ position until is switched back on.

Dip switches can be found in old electronics, but nowadays, they can also be found in garage door openers, and they are used to control multiple circuits at once.

There are rocking or rocker switches, toggle or knife switches, rotary switches the can be activated by rotary or key turning (car ignition), snap action (a button pressed by a lever), and there are also switches that react to environmental stimuli. This type of switches include: photo diodes and photo resistors (react to light), thermistors (react to heat or temperature), proximity sensors (react to movement or distance).

There are also pressure sensors, switches that react to magnetism (reed switches or relays), and there are also sensors that react to sound.

These types are often reffered to as sensors, but they can still be used as switches.

There are also switches that don’t use physical movement to actuate and to close the electrical circuit. These switches are contacts printed directly onto a PCB, and they use covers that connect the contacts when pressed. Video game controllers use this type of switches.

Lots of buttons and switches have a cover or a membrane to make the interface easier and more comfortable to use.

Conclusion

There are a lot of switches out there, but the most common ones have been discussed above and they are used in our everyday life all the time.