international standard in the world, which is divided into FMS, DP and pa
Level III, DP communication rate can be up to 12MB. PROFIBUS is used to connect distributed i/0 stations, field bus instruments and other intelligent devices.
The communication among process station, operator station and engineer station is realized through the system bus diginets (Industrial Ethernet). user
Different transmission media (RJ45 twisted pair, thin cable, thick cable or optical fiber cable and mixed media) and network topology can be selected for the system bus
Due to the adoption of tcp/ip protocol, the system can also realize ultra long distance communication with the help of public telephone network (dial-up mode) or satellite.
PLC and other subsystems communicate with industrial “system through Modbus protocol interface. The system also supports iec870-5 over control coordination
Discussion.
The flash EPROM inside PS provides more than 220 function modules (control algorithm subroutines), in addition to the base specified in IEC 61131 3 standard
In addition to this content, many powerful and strictly tested function blocks from practical engineering applications are also expanded. Any complex control
All schemes can be realized by the combination of these function blocks.
The function blocks provided by the system mainly fall into the following categories:
o
Analog quantity processing
o
Digital quantity processing
Loop adjustment
Logical sequence control
c
Logical operation
Monitoring function
Acquisition function
c
Arithmetic operation
c
Tcp/ip protocol communication interface
Modbus protocol communication interface
1ec870-5 protocol communication interface (telecontrol)
4.2 field controller PS
Industrial ial “field controller PS is a special process control station, which is embedded with a fieldbus communication interface for users to use
