The working principle of the servo motor encoder

Servo motor encoder the basic functionality is the same with normal encoders, such as absolute type has A, against A, B, B, Z, Z signals, such as, in addition, there are different from ordinary encoder servo motor encoder, it is that most of the servo motor encoder for synchronous motor, synchronous motor startup needs to know the rotor magnetic pole position, such ability can big start torque servo motor, so need another with A few road signals to detect the rotor current location, such as the incremental model has A signal, such as the sale and because of this A few way to detect the rotor position signal of servo encoder seem A bit complicated, so that ordinary people can't understand it's truth, plus some manufacturer intentionally mask covered some of the signal, and the relevant information is not complete, is even more mysterious color added the servo motor encoder. Because of A, B two phase difference of 90 degrees, but only through A phase in the former or B phase in the former, with forward and inversion of discriminant encoder, through the zero pulse, encoder zero reference can be obtained. Encoder code disc material with glass, metal, plastic, glass encoder is in the deposition of thin scribed line on the glass, its thermal stability, high precision, metal encoder directly to scribe lines and impassability, non-friable, but because has certain thickness of metal, precision is limited, its thermal stability is an order of magnitude worse than glass, plastic encoder is economical, its cost is low, but the accuracy and thermal stability, life is less. Encoder resolution per 360 degrees provide much or dark scribed line called the resolution, also known as the analytical index, or say how many line directly, generally at every turn dividing line 5 ~ 10000.