A single-pole, single-throw ( SPST ) switch is as simple as it gets. The switch will either be closed or completely disconnected. SPSTs are perfect for on-off switching. SPST switches should only require two terminals. Pole refers to the number of circuits controlled by the switch: SP switches control only one electrical circuit.
DP switches control two independent circuits (and act like two identical switches that are mechanically linked).
These terms have given rise to abbreviations for the types of switch which are used in the electronics industry such as single-pole, single-throw ( SPST ) (the simplest type, on or off) or single-pole, double-throw ( SPDT ), connecting either of two terminals to the common terminal. It has two separate common terminals and each of those is connected to one or the other of the other two terminals on the same side of the switch. The dotted line in the picture is to illustrate that. Add all three to Cart Add all three to List.
This is an article explaining what a single pole single throw ( SPST ) switch is and how it is used in a circuit. A dpdt circuit symbol, and a terminal dpdt rocker switch pole refers to the number of circuits controlled by the. Fundamentals of Power Electronics.