This example demonstrates how to use the two analog adjustments (potentiometers, or POTs) of the SIMATIC S7-200 CPU. The positions of the potentiometers are converted into digital values between 0 and 255. The value for analog adjustment 0 is stored in special memory byte SMB28; the value for analog adjustment 1 is stored in special memory byte SMB29. A small screwdriver is required to adjust the positioning. This application tip demonstrates three ways to use an analog potentiometer to adjust the Preset Time (PT) of a timer.
