The marking of potentiometers generally adopts the straight labeling method. That is, they are directly marked on the potentiometer with letters and numbers. The contents marked generally include the model, category, nominal resistance and rated power of the potentiometer. Sometimes the potentiometer also marks the code of the output characteristic of the potentiometer (where z represents the exponent, D represents the logarithm, and X represents the linearity).
The role of potentiometer
The main function of the potentiometer in the circuit is to divide the voltage. In addition, the potentiometer can also be used as a varistor and current controller.
Used as a voltage divider
The potentiometer is a continuously adjustable resistor. When the rotary or sliding handle of the potentiometer is adjusted, the moving contact slides on the resistor body. At this time, at the output of the potentiometer, an output voltage that has a certain relationship with the applied voltage of the potentiometer and the angle or stroke of the movable arm can be obtained.
Used as a rheostat
When the potentiometer is used as a varistor, it should be connected to both ends of the device, so that within the travel range of the potentiometer, you can obtain a smooth and continuously changing resistance value.
Used as a current controller
When the potentiometer is used as a current controller, one of the selected current output terminals must be the sliding contact terminal.