What is a Double Pole Single Throw (DPST) Switch?

Double Pole Single Throw (DPST) Switch

A Double Pole Single Throw (DPST) switch is a switch that has 2 inputs and 2 outputs; each input has 1 corresponding output.

Double Pole Single Throw (DPST) Diagram

Each of the terminals of a double pole single switch can either be in the on position (closed) or in the off position (open).

A Double Pole Single Switch has a lot of versatility being that it accepts 2 inputs, which makes it then be able to drive 2 different outputs in a circuit. What it drives depends on the circuit design and what the circuit is intended to do. But DPST have enormous applications in circuits.

Double Pole Single Throw Switch (DPST) Circuit

Below is an example of a circuit which utilizes a double pole single throw switch.

Double Pole Single Throw (DPST) Switch Circuit

You can see above how a double pole single throw switch can be used to put a circuit in any of 1 of 2 modes. When the switch is connected one way for circuit A and circuit B, the lamp and LED will both be ON. When connected the other way, the lamp and the LED are both OFF.

So a DPST switch allows for control of 2 outputs, turning either both on or both off together.

Related Resources

Single Pole Single Throw (SPST) Switch

Single Pole Double Throw (SPDT) Switch

Double Pole Double Throw (DPDT) Switch