Heavy Duty: Designed to survive some of the toughest environments. Using magnetic, inductive or specially designed optical technology, their tight sealing, heavy-duty bearings and high temperature range make them well suited for use in harsh environments.
Industrial Duty: The workhorse of the encoder world, these encoders achieve a good compromise between ruggedness and performance. Used in factory environments where contaminants like dust and moisture are common.
Light Duty: Often referred to a commercial duty due to their frequent use in commercial or office automation products. Used in applications with little temperature variation, are fairly clean and not generally subjected to high shock loading or moisture.
Servo Duty: Specifically suited to use on small- to mid-size stepper and servo motors. They have limited sealing due to their use inside motor housings, but are capable of very high speeds and high temperatures. They typically come ready to mount to common motor back shafts.