Absolute rotary encoders provide a distinctly coded numerical value for each shaft position. In positioning tasks in particular, the absolute encoders relieve the controller of computation tasks and keep costs down by eliminating the need for additional input components.

Moreover, reference runs when the machine is switched on or after power failures are no longer required as the current position value is available immediately. Parallel absolute encoders transmit the position value to the analyzing electronics through several parallel cables.Serial absolute encoders transmit their output data via standardized interfaces and protocols.

In the past, point-to-point connections were frequently set up for serial data transmission but today fieldbus systems are being used more often.