How PLC communication with the other software

[tang6518]

I'm a novice at PLC. so maybe the question is very easy. but I really want to know.
How PLC communication with the other software ?
sometimes somebody told me, PLC connected to server via the 100baseT Repeater.the software which installation in the server will can send the data to the PLC .
If the above is true , which detail is in the inner ?
Thanks !

 

[userxyz]

PLC connection to software

The physical connection from a PLC to a PC kan be ethernet, serial, profibus, whatever communication.

Communication to VB.net, Office or other wondows software can be done with an OPC server. This is a piece of software that runs on a PC and has the task to read and write PLC variables. The OPC server can be reached by windows software. In the case of HMI or Scada softwares, mostly there are standard I/O drivers for these. Wonderware for example has DASI-Direct server, it's and I/O server that has the task to read and write PLC variables. A Wonderware Scada can be installed on the same machine or another machine and linked to the I/O server. In the case of Siemens for example, WinCC has a standard S7 driver to support their own PLC's. For other connections they have standard drivers, but connecting an OPC server is also possible.

Sonno if this helps something...

I'm a novice at PLC. so maybe the question is very easy. but I really want to know.
How PLC communication with the other software ?
sometimes somebody told me, PLC connected to server via the 100baseT Repeater.the software which installation in the server will can send the data to the PLC .
If the above is true , which detail is in the inner ?
Thanks !

 

[tang6518]

Thanks , Combo.
another question, now our situation is the SQL sever to write the data to PLC.then SQL sever can read the PLC bits status. PLC didn't connected to SQL sever directly but via 100baseT Repeater.
so.can I know this system how to work ?