Ring encoders are large diameter rotary or angle encoders, which provide position and speed feedback in rotary movement applications. Most ring encoders are based on optical technology and use a ring shaped optical grating which rotates relative to a stationary optical sensor.
Optical ring encoders are well suited to high precision applications where the rotor can be accurately installed relative to the sensor or read head and where there is no possibility of dust or foreign matter interfering with the optical path.In harsh environments, optical ring encoders can prove unreliable.
Zettlex ‘IncOder’ inductive encoders have a similar physical appearance and mounting format to traditional optical ring encoders, and are often referred to as inductive ring encoders. However, instead of an optical technique, IncOders use a transformer or inductive technique. IncOders have 2 main parts – a powered Stator and a passive Rotor – each shaped like a flat ring. The output signal from the Stator shows the true absolute position of the Rotor relative to the Stator without the need for any motion.
Whereas optical ring encoders can be unreliable in harsh conditions – notably with condensation or dust – IncOders are generally unaffected by foreign matter, making them ideal for use in harsh environment applications.
IncOder ring encoders have no contacting, delicate or wearing parts, so there is no need for periodic replacement, service or maintenance. Their ring-shaped construction makes it easy to accommodate through-shafts, slip-rings, optical fibres, pipes or cables.
Fig.1. Zettlex IncOder ring encoders are well suited to harsh environment applications where dust and moisture are present; unlike standard optical ring encoders.