PLC(可编程逻辑控制器)In the sequence controller and microcomputer controller developed on the basis of the controller. Its high reliability, simple and intuitive way of programming, and more and more perfect function makes it has been widely applied in industry control field. Among them, in a lot of automatic control system by PLC to control the step motor, when the PLC send pulse signals and direction, the stepper motor drive through PLC receives the pulse output pulse signal and the signal to control the stepper motor work direction, a pulse signal can make the stepper motor rotation Angle of a fixed, so there must be some relation between pulse number and frequency, frequency curve of step motor intuitive reflect this relationship. In the development of automatic Chinese traditional medicine distribution system and development of the number of pulses through the PLC control of stepping motor, ensure the take medicine to take medicine correctly location take medicine. If the number of pulse and frequency Settings, take medicine the car speed is slow, not only may also occur jitter, noise big, to speed up the adverse factors such as machine wear, which affects the working efficiency of the whole system, thus optimize the frequency curve of step motor is very be necessary. PLC is divided into fixed and modular (structurallyModular)。 Fixed PLC including CPU boards, I/O board, display panel, memory blocks, power supply, etc. ; Modular PLC, including CPU module, I/O module, memory, or the chassis, power supply module, the module can be according to certain rules of combination configuration. CPU is the control center of the PLC, by arithmetic unit, controller, register, and achieve them link between data bus, control and state. Into modules by receiving and collection into the signals to the CPU processing; Output module receives the information and successfully processed by the CPU control contactor, digital display device and output equipment. In addition, the PLC programming device used to naturally user program, commonly used handheld programming is used to give a small PLC programming, usually by computer,Programming software)Act as. The international electrotechnical commission (IEC)In 1994 published the PLC programming language standard (IEC113123), the standard defines the five PLC programming language: ladder diagram LAD (梯形图), statement table STL (本月吵闹列表), the function block diagram FBD (功能块图)ST, structure, text (圣生成文本), sequence function diagram SFC (顺序功能图)。 Use programming software can be directly on the screen are naturally and ladder diagram, sequence diagram editor program, and can realize the mutual transformation of different programming languages, program is compiled to download to the PLC's memory. PLC adopt the way of 'sequential scan, cycle', according to the user program memory, and CPU step according to the instruction sequence number (Number or address)A periodic cycle scanning, without interruption or jump instruction, the CPU start in order to perform a detailed program, for each signal between the logic operation, finally the results written into the output image register process, signal after output module isolation and power amplification, type relay output module of the corresponding hardware relay coil electricity, electricity work so that the external load. the main products: stepper motor, brushless motor, servo motor, stepping motor drive, brake motor, linear motor and other kinds of models of the stepper motor, welcome to inquire. Telephone: