Yuheng Optics Co., Ltd.(Changchun)

Yuheng Optics Co., Ltd.(Changchun)

Servo motor encoder absolute and incremental difference

2023 01/23

An encoder is a device that compiles and converts a signal (such as a bit stream) or data into a form that can be used for communication, transmission, and storage. The encoder converts an angular displacement or a linear displacement into an electrical signal, the former being called a code wheel and the latter being called a code ruler. According to the readout mode, the encoder can be divided into contact type and non-contact type; according to the working principle, the encoder can be divided into two types: incremental type and absolute type. The incremental encoder converts the displacement into a periodic electrical signal, which is then converted into a counting pulse, and the number of pulses is used to represent the magnitude of the displacement. Each position of the absolute encoder corresponds to a certain digital code, so its indication is only related to the start and end positions of the measurement, regardless of the intermediate process of the measurement.

Incremental servo motor encoder introduction

Incremental coding In addition to the ABZ signal of the ordinary encoder, the incremental servo encoder also has a UVW signal. Most of the domestic and early imported servos use this form, and the lines are more.

The incremental encoder outputs a pulse when it is rotated, and its position is known by the counting device. When the encoder is not moving or power is off, the internal memory of the counting device is used to remember the position. In this way, when the power is off, the encoder can't have any movement. When the caller works, the encoder can not interrupt and lose the pulse during the output pulse. Otherwise, the zero point of the counting device will shift, and this bias The amount of shift is unknown, and only the wrong production result can be known.