Other modules

There also are additional modules for specific purposes. These include the following:

• Proportional-Integral-Derivative (PID), to which the PLC provides just the required value or the SP for the process value. The PID autonomously calculates the value for which the controlled value fits the SP.
• Servo modules, that directly and independently perform the interlocking of one or more stepper motors, hydraulic motors, or direct current motors with incremental encoders.
• Encoder modules, that realize all of the functions that are necessary to use in one or more incremental or absolute encoders. These are essentially modules with high-speed counters.