In PLC sine inverter application Mitsubishi modern PLC sine inverter application Mitsubishi industrial control system, PLC and frequency converter of the integrated application of the most common. Compare the application of traditional general is the use of PLC output contact driver intermediate relay to control start, stop, or more sections of A frequency converter speed, PLC and D/A extension module controls the frequency of the inverter. By D/A expansion module controls the frequency of the inverter, vulnerable to the volatility of the analog signal and the distance from the analog signal attenuation caused by inconsistent inconsistent effects, reduce the working stability and reliability of the whole system. To consider from economic Angle, when more than the need to control frequency converter, using D/A extension module, the cost would be to use the RS - 485 communication many times, for example: A FX2N - 2 da (two lines of analog output module) price in 1000 yuan of above, and A FX2N - 485 - bd (FX series 485 communication board) price in 200 yuan. Using RS - 485 communication control, it is easy to realize the inverter synchronous and proportion between linkage operation. The system has low cost, signal of high precision (up to highest frequency converter resolution), transmission distance, strong anti-interference, etc.
Second, the system configuration
Rubber roller machine control system using 3 frequency converter, walking respectively control the car, the spindle, the speed of extruder. Requirements are divided into automatic/manual control, touch screen interface for the boot interface manual, automatic and manual/automatic choose four interface; Automatic state through the choice of different proportion to the touch screen control three frequency of frequency converter and start-stop, Operated manually state can be individually with three positive &negative and frequency converter.
Three, the system hardware composition and the connection
According to the control requirements of the system, choose the following device
1, PLC selection Japan mitsubishi FX1N - 14 Mr;
2, PLC485 communication extension board FX1N - 485 - BD (with frequency converter for communication);
3 256 color touch screen, touch screen for WEINVIEWMT5005.7 inch;
4, touch screen with PLC connection cables;
5, inverter with my company independent research and development of sine SINE303 series inverter, have low torque, load ability, perfect protection function etc;
Fourth, communication protocol
Sine inverter built-in standard RS - 485 communication interface, protocol format as follows:
Data in baotou: 02 h (data in baotou starting bytes)
From the machine address: frequency converter for the machine, the machine address of frequency converter which is a PLC communication from the machine address, by the parameters of the frequency converter set (host for industrial control computer and PLC programmable controller, etc.).