Incremental rotary encoder is the direct use of photoelectric conversion principle square wave pulse output three groups A, B and Z phase; A, B two pulse phase difference of 90 degrees, and thus can easily determine the direction of rotation, and Z for each phase a transfer pulse for homing. The advantage is that the principle of simple structure, mechanical average life of more than tens of thousands of hours, anti-interference ability, high reliability, suitable for long distance transmission, the drawback is absolute position information can not be output shaft rotation.
First, the incremental rotary encoder has a resolution of differences, the number of pulses per revolution generated by using the measured number from 6-5400 higher, the number of pulses or more, the higher the resolution; this is an important basis for selection one.
Second, the incremental rotary encoders usually have three-way signal outputs (differential six signals): A, B and Z, the general use of TTL level, A pulse front, B pulse after, A, B pulse difference of 90 degrees, issue a Z pulse per revolution, as a reference mechanical zero. A general use leads B or B leads A to be sentenced, I incremental rotary encoder is defined as the encoder shaft clockwise to look forward, ahead of A and B is 90 °, counterclockwise rotation and vice versa for the reverse B A lead of 90 °. There are not the same, depending on the product description.
Third, the use of PLC data collection, the choice of high-speed counting module; use the IPC data acquisition, high-speed counting cards can be used; the use of SCM data acquisition, we recommend the use of optical input port coupler.
Fourth, the proposed B pulses do forward (forward) pulse, A pulse to do the reverse (backward) pulse, Z datum zero pulse.
Fifth, the establishment of a stack count in the electronic device.