In plc analog input modules to control the role played

Power systems using conventional crane relay - contactor control, but this control system has some drawbacks:
The first day, the need for a large number of loading and unloading  plc programmable logic controller operations, switching frequency, in the current state of the larger, easy to burn contacts; Second, poor reliability, complex operation, failure rate, energy waste and inefficiency.
Third, in order to adapt to the working conditions of crane, crane operator frequent repeated handling, high-current electrical components always in working condition, reducing the life of the electrical components and motors.
Fourth, the coordination of the work depends mainly on the crane operator's proficiency. When the crane operator labor intensity of work is relatively large, easy fatigue, prone to misuse.
Solve these problems, only to completely change the traditional control  plc power supply module methods fundamentally. In recent years, with the rapid development of computer technology and power electronics, electric drive and automatic control field is also changing. Among them, a representative of the PLC to obtain a wide range of applications in the crane control system provides favorable conditions.
In the PLC-controlled crane ready to set the speed according to the scene at work, time and deceleration time upshift; improve work efficiency, more accurate positioning; energy-saving effect is obvious, saving rate of 35%; gear, Motor shock, low failure rate, easy to maintain, greatly reducing maintenance role; improve the reliability and modular plc  safety of traffic, extending the life of the crane.