An absolute encoder is a position sensor that outputs the actual angular position. The word “absolute” refers to how the angle is measured against an internal reference. If power is interrupted, the device retains its position. When power is restored, any motion that occurred while it was off is reflected in the reported angle without the need to re-home.

Incremental encoders, by contrast, report relative motion in discrete counts and start from zero at each power-up. This reset behaviour is less suitable for tight-tolerance positioning, so absolute encoders are generally the better choice where high accuracy is required.

● Provide high-precision feedback of true angular position. Available with multiple interfaces such as SSI, CAN and Ethernet.

● Designed for harsh conditions. They operate reliably under extreme temperatures, shock and vibration, and in the presence of liquids and contaminants.

● Many models are multi-turn, tracking position over several full revolutions. This suits measurements that exceed 360 degrees.

● No homing after a power cycle. Avoiding a return-to-zero step is a major benefit in many machines.