The rotary encoder is based on the precise measurement of the angular displacement sensor principle of electromagnetic induction, can be used to measure the rotational speed of machinery, mechanical devices can also be speed, speed machining sometimes need to change, you can use the rotary encoder to work in. so how to properly install the rotary encoder it?
　　Common rotary encoder has five leads, where 3 is a pulse output line, a COM is the end line, a power cord (OC gate output type). Power source may be an external power supply, can also directly use the power of the PLC. Power "-" terminal to be connected with COM encoder "+" power supply terminal and encoder connections. COM of the encoder and the PLC COM input terminal is connected, A, B, Z two-phase pulse output is connected directly to the input of the PLC, A, B is 90 degrees pulses. There is a rotary encoder shielded cable, the use of shielded wire to the ground, improve immunity.
　　Rotary encoders installation procedures and installation considerations 　　1. Make sure to firmly install the encoder, in order to avoid vibrations caused by loose;
　　2. When the encoder shaft and the machine shaft coupling, make sure the load shaft must not exceed its maximum allowable value;
　　3. When the encoder shaft through the coupling and the machine shaft coupling, make sure that there is no bias;
　　4. Do not link with rigid coupling;
　　5. Requests the coupling locking screws to avoid loosening during use;
　　6. Select the appropriate coupling, the coupling is also increased because the weight of the load shaft;
　　7. When the belt coupling, with a timing belt, or the angle transmitted inaccurate;
　　8. When a timing belt, make sure that the belt tension is appropriate in the course of the belt installation and note loose.;
　　9. Avoid during rotation of the pulley radial loads cause vibrations and deviations;
　　10. When the encoder shaft and the machine shaft with a gear coupling, avoid radial loads cause part or whole vibration gear;
　　11. Do not be struck by the encoder couplings, belts and gears;
　　Vibration coupling 12. The shaft should be controlled 0.1T.I.R.

Through knowledge as a rotary encoder installed regard, I believe we should pay attention to the installation process issues have a general understanding of the installation using these issues into account, it is safe to operate the rotary encoder.