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Lead Contents

Rotary Encoders

Rotary Encoders measure the number of rotations, the rotational angle, and the rotational position. Linear Encoders are also available to measure linear movement.

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Primary Contents


Selection Guidelines

1. Incremental Encoder or Absolute Encoder?

Select a type that is suitable in terms of the cost vs. capacity, returning (or not) to the origin at startup, the maximum speed, and noise tolerance.

2. How much resolution is needed?

Select the optimal model in view of required precision and cost of machine equipment. We recommend selecting a resolution of from 1/2 to 1/4 of the precision of the machine with which the Encoder will be used.

3. Dimensions

Also take into consideration the type of shaft that is required (hollow shaft or regular shaft) in relation to mounting space.

4. Permitted Shaft Loading

When selecting, take into consideration how the mounting method affects the load on the shaft and mechanical life.

5. Maximum Permissible Speed

Base your selection on the maximum mechanical speed during use.

6. Maximum Response Frequency

Base your selection on the maximum shaft speed when the device in which the Encoder is used is in operation.
Maximum response frequency = (Revolutions (RPM) /60) x Resolution.
There are deviations in the actual signal periods, so the specifications of the selected model should provide a certain amount of leeway with respect to the above calculated value.

7. Degree of Protection

Select the model based on how much dust, water, and oil there is in the application environment.

Dust only: IP50

Water or oil also present: IP52(f), IP64(f) (water-resistant, oil-resistant)

Oil present: Oil-proof construction

8. Startup Torque of Shaft

How much torque does the drive have?

9. Output Circuit Type

Select the circuit type based on the device to be connected, the frequency of the signal, transmission distance, and noise environment.
For long distance transmission, a line-driver output is recommended.