Resolvers

Several technologies are available for position sensing in industrial environment. The two most popular devices for sensing rotary position are encoders and resolvers. Resolvers are preferred sensing devices in the industrial environment due to their robustness.

Advantages of Resolvers vs. Encoders

The decision of whether to use a resolver or encoder depends entirely on the application. The factor that has the greatest impact on the decision is the operating environment. The environmental integrity of a brushless resolver is unchallenged. Being simple rotary transformers, resolvers can take more abuse than optical encoders.

Resolvers exhibit no significant wear or aging. This is especially important when the operational temperature is below freezing or above 150 F. Under these extremes, the only choice is to use a resolver. The operating temperature of a typical resolver ranges from -67 F to +248 F. Resolvers also survive in conditions of severe mechanical shock and vibrations, excesses in humidity, oil mists, and exposure to coolants and solvents.