Views: 0 Author: Site Editor Publish Time: 2024-06-06 Origin: Site
The Linear accuracy and the pulse accuracy of encoder
Linear accuracy refers to the error between the measured value and the actual displacement value (distance). It reflects the measurement accuracy of the measuring device over the entire range, especially when approaching the range limit. The calculation formula for linear accuracy usually involves the difference between the theoretical value and the actual test value, expressed as a percentage. For example, if the linear accuracy of the full range is 0.1%, it means that the maximum error between the measured value and the actual value over the entire range will not exceed 0.1% of the full range.
For example, for a range from 0 degrees to 90 degrees (requiring a deviation of less than 0.002 degrees), from 0 degrees to 180 degrees (requiring a deviation of less than 0.002 degrees), and from 0 degrees to 270 degrees (requiring a deviation of less than 0.002 degrees), these are the requirements for linear accuracy.
If there are no such requirements and only a single pulse is required to be less than 0.002 degrees, it is referred to as pulse accuracy.
The pulse count of an encoder refers to the number of pulses output by the encoder per revolution, which is an important indicator of the encoder's accuracy. The higher the pulse count of the encoder, the smaller the angle represented by each degree, and the higher the accuracy. For example, for an encoder with a pulse count of 1000, it outputs 1000 pulses per revolution, and each pulse represents an angle of 360/1000 = 0.36 degrees. On the other hand, for an encoder with a pulse count of 500, each pulse represents an angle of 360/500 = 0.72 degrees, resulting in lower accuracy. Therefore, to improve the accuracy of the encoder, a higher pulse count encoder is usually used.
