Shaft vs. Bearingless Encoders

Depending on the application, there are several reasons why using a bearingless encoder may be more suitable than a shaft encoder. There are several benefits to each, which makes them ideal for different applications depending on your requirements.

Watch Dynapar's video on the "Benefits of Bearingless Encoders" where we showcase our RIM Tach 8500 NexGen and our New SLIM Tach ST56 bearingless encoders.

Applications for Bearingless Encoders

There are several different applications for bearingless encoders, depending on what you need them for. If you need an encoder for a harsh environment, bearingless encoders are often used in applications such as pulp and paper mills and outdoor applications where contaminants, extreme temperatures, shock, and vibration are present. Without bearings included in the encoder design, this also means there is one fewer item that can fail over time as a result of wear.

Applications for Shaft Encoders

Applications for shaft encoders, on the other hand, include a range of less adverse environments that require feedback solutions with flexible mounting options. In many cases, design engineers will use these encoders, but bearingless encoders may be better suited to avoid gradual wear and survive contaminated environments.

Benefits of Bearingless Encoders

While some applications may call for a shaft encoder, it can be an additional point of failure in harsh applications that demand maximum reliability. Dynapar bearingless encoders also use magnetic sensing technology which is far less susceptible to dirt, grease or water impacting the quality of feedback as compared to a shaft encoder using optical sensing technology where these contaminants can impair the optical encoder’s code disc.

Dynapar Bearingless Encoders Featured in this Video:

RT8 Bearingless Magnetic Encoder

  • Most tolerant digital tachometer to motor shaft run-out with the largest non-contact sensing gap in the industry (0.075")
  • On-board diagnostics with LED and alarm output for immediate identification of signal disruption
  • Dual output with isolated electronics option available for redundancy in mission-critical applications
  • Optimized pulse wheel for greater shaft holding force and ease of assembly

ST56 Bearingless Magnetic Encoder

  • Most tolerant digital tachometer to motor shaft run-out with the largest non-contact sensing gap in its class (60 thousandths)
  • Most compact bearingless solution with thin 3/4" profile and 9.8" height ideal for space-constrained motor feedback applications
  • Dual output with isolated electronics option available for redundancy in mission-critical applications
  • On-board diagnostics with LED and alarm output for immediate identification of signal disruption