Add-on blocks for Modbus/TCP communication
This involves the following products.
|Modbus/TCP CP RED||6AV6676-6MB30-3AX0|
|Modbus/TCP RED V2||2XV9450-1MB11|
|Modbus/TCP PN CPU||2XV9450-1MB02|
|Modbus/TCP PN RED|
Frequently, adaptations are required when implementing Modbus/TCP communication in a larger plant or system, for example:
- For communication with Modbus/TCP blocks, more data should be sent to a partner than is possible using a single telegram.
- The Modbus data to be sent or read is saved in global data blocks. However, when using CFC, global data blocks are often not wanted.
- In some plants and systems, it is specified that all the machine data - independent of the data type - is saved in a single data block.
These adaptations can be implemented in a user-friendly and convenient fashion by using the blocks provided in the "Additional Modbus Blocks" library.
- The "Job List" block allows several different Modbus telegrams to be cyclically processed.
- "Data Collectors" blocks can be inserted in a CFC chart by dragging & dropping them. There, they are directly interconnected with the Modbus block to process Modbus data.
- Using the "Marshalling Blocks" data that has been received or is to be sent with various data types (Holding Register, Input Register, Coils, Inputs) can be marshalled in a single data block.
"Additional Modbus Blocks" library for STEP 7 V5
The "Job List" library for STEP 7 V14 SP1 or higher
The "Job List" block is available as global library, also for STEP V14 SP1 or higher . Unzip the library to a directory of your choice. Open STEP 7. You can integrate the unzipped library under "Library > Global libraries > Open global library". The block is available in the SCL and STL programming languages.
Update of the documentation of the "Additional Modbus Block" library for STEP 7 V5