Technical Blog

What is an Absolute Encoder?

An encoder is a device used for measuring angle position. They can be used within many different devices which are vital in various industries and applications.

An absolute encoder is a type of encoder. Absolute refers to how an angle is measured. an Absolute encoder measures absolute or true angle position. If the power to the encoder is switched off it will retain the measured angle and if a movement is made with no power, the encoder can still measure this once power is returned.

This is different to the way Incremental encoders work. Incremental encoders measure angles in increments and can only give measurements on the change in position. Each time the encoder is switched on measurements will start at zero. This makes them less suitable for high accuracy applications whereas Absolute encoders are perfect for high accuracy.

Why choose an absolute encoder?

Absolute encoders are often selected for their high accuracy, giving feedback on true angle position. They have different output options including SSI/CAN/EtherNet.

Absolute encoders are also extremely robust making them suitable for a variety of applications in different industries. They can withstand extreme temperature, shock, vibration as well as fluids and foreign matter.  

Absolute encoders tend to cost more than Incremental encoders, but this is understandable due to the difference in accuracy and principle.

Absolute encoders can also be multiturn meaning they can take measurements over more than one full 360-degree rotation. This makes them suitable for applications where this is required.

The fact that an absolute encoder doesn’t have to return to zero when power is returned is another reason for selecting an absolute encoder for an application. This can be essential for many systems.

The Absolute encoders we can offer come from our supplier Wachendorff, they have a patented technology called Endra which allows the encoders to have;

  • No battery back-up or gear function
  • No traditional optical disk, thus reducing the component costs associated with this.
  • High resolution with up to 16 bit single and 43-bit multi-turn.

Typical applications for absolute encoders

Applications for absolute encoders can be within many industries. One of the upcoming and increasingly popular areas for Absolute encoder us Is within Robotics.

Robotics is present within many manufacturing areas, welding, paint spraying and various assembly and packaging processes. Encoders are well suited to accurately measure robotic arm angles and other processes.

They are also well suited to applications such as

  • Cut to length applications
  • Radiation therapy
  • Bottle ration applications – for filling and labelling
  • Various printing applications
  • Positioning within elevators
  • Satellite communications
  • Automation on assembly lines
  • Various packaging machines
  • Surgical robotics

Absolute encoders from Variohm

All of our absolute encoders can be found on this page of our website https://www.variohm.com/products/position-sensors/absolute-rotary-shaft-and-hollow-shaft-encoders

For more information on help selecting the right product for you then please contact us.

Article published on: 10/02/2022