What exactly is the difference between incremental and absolute encoders? An absolute encoder can tell you the exact position of the shaft in its rotation at any given time (and how many rotations have transpired on a multi-turn absolute encoder). An incremental encoder can only report a change in position. It may not sound like a big difference, but it's night and day if the system has a loss of power. Once power is restored, an absolute encoder can report exact position without any movement. An incremental encoder will need to find an Index or home position before it can do so – and if it doesn't have an index, it won't be able to tell you it's position at all.

