SIMATIC PLC is the Germany Siemens company launched in 1995, high performance-price ratio of the PLC system. Which micro-SIMATIC S7-200 series, 8DI/6DO is the minimum configuration, scalable 2~7 module, maximum I/O point numbers 64DI/DO, 12AI/4AO. Small and medium of SIMATIC S7-300, S7-400 series of high-end properties. PLC SIMATIC S7 series are modular, no exhaust fan … Continue reading SIMATIC S7 PLC overview

SIMATIC S7-300 PLC is a modular design, widely various between separate modules that can be combined and extended. The main components of the system include: 1) central processing unit (CPU): SIMATICS7-300 provides a wide range of different performance of CPU in order to meet the requirements of different users, including CPL3121FM, CPU313, CPU314, CPU315, CPU315 2 … Continue reading Composition of the SIMATIC S7-300

S7-300 's modular structure, can be different according to the application object, use of different models and different number of modules, and modules can be installed in the same rack (rail) or on more than one rack. Matching with the CPU3121FM and CPU313 modules can only be installed in a rack. In addition to the … Continue reading S7-300 scalability

S7-300 CPU has three basic storage, including: (1) the system storeTypes of RAM used to store operational data (I/O, memory, timer, counter, etc). (2) Mount StoreCPU module is part of the physical RAM, plus a built-in EEPROM or optional removable EEPROM cards, used to store user programs. (3) the work storeConsume CPU module part of the physical RAM, … Continue reading S7-300 introduction to PLC store

S7-300 has a variety of different communication interfaces, notably the following: 1) multiple communications processors to connect to the as-I interface, PROFIBUS and Ethernet bus systems. 2) serial communications processor is used to connect to a point-to-point communication system. 3) multi-point interface (MPI) integrated in the CPU, for connected programmer, PLC HMI systems and other automated control systems … Continue reading S7-300 communications

Ports 1 and 2 enter 3 type signals. For high speed counters 1 and 2 input mode is set in the DM6643 and DM6644, respectively. 1) phase difference mode (count rate =25kHz): 4x2 signal phase difference (phase a and phase b) and z signal for input. According to the phase 2 signal count increment or decrement. … Continue reading CQM1 PLC high-speed counter input 1 and 2 mode

High speed counter counts 1 and 2 mode (circular or linear mode) specified in the DM6643 and DM6644, respectively. 1) ring-shaped pattern. Ring mode, CTBL (-) set the maximum count value in +1. Increment the counter when the maximum count value to 0, when declining counters count from 0 to the maximum value, not negative.Ring of points … Continue reading CQM1 1 and 2 the count of PLC high-speed counter mode

When you reboot, you must use a method to reset the counter, when starting or stopping program execution, automatic reset of the counter. You can choose z signal + software reset or a software reset to reset the count of PV (set to 0), reset the same as high-speed counter 0.

There are 2 ways to read PV value, 1th from SR232 and SR233 (port 1) or SR234 and SR235 (port 2) read the 2nd use PRV (-) instructions.1) read SR232 and SR233 or SR234 and SR235.High speed counter 1 PV is stored in SR232 and SR233, high speed counter 2 PV is stored in SR234 … Continue reading CQM1 1 and 2 read the PV value of PLC high-speed counter