SPDT and DPST Switches
There are four common switch types, today EPCB will go over the other two of them-- SPDT switch and DPST switch.
Single Pole Double Throw Switch: A single pole double throw or SPDT switch only has a single input. Unlike SPST and DPDT switches, SPDT is able to connect and switch between 2 outputs, which means that it has 1 input terminal and 2 output terminals. A SPDT switch can perform various functions in a circuit, for example, it can serve as an on-off switch, or it can used to connect circuits to any 2 various paths that a circuit may need to function in. The above picture 1 vividly shows the two-connection mode allowed by SPDT switches.
Double Pole Single Throw Switch: A double pole single throw or DPST switch has 2 inputs and 2 outputs, and each input has 1 corresponding output. Each of the terminals of a DPST switch can either be in the on position or in the off position. DPST can be used in a variety of applications in circuits, that’s because a DPST switch has 2 inputs, and each can be connected to 1 of 2 different outputs in a circuit.