The Single Pole Double Throw (SPDT) Switch basically has only two terminals. The middle terminal is the input terminal, and the terminal on the left or right is the output terminal.
The conventional wiring method is as follows: connect the live wire or the positive terminal to the middle input terminal, and connect the output terminal to one terminal of the device. Finally, connect the other terminal of the device with the other end of the input terminal to the power supply.
Single Pole Double Throw (SPDT) Switch Circuit
Here is an example of a circuit diagram for a single-pole single-throw switch controlling a light bulb.
At the same time, you can replace the above light bulb with your corresponding device.