Redundant PLC
Posted: Fri Oct 24, 2014 8:00 am
I have stuck on one problem. Saw similar one question on iX forum, unfortunately didn't find any answer.
The question is about redundant PLC (Siemens S400). Using manual I've configured them as you can see in attached picture. Selected S7 ISO TCP/IP protocol. In tag list connected them to different address (example:
0:DB30.DBX0.4
1:DB30.DBX0.4
to read the PLC status (Master or Stand by) . When the HMI panel (T15BR) start up, system read all data correctly, but when I switch over PLC, HMI don't update tag status, no matter which PLC is master and no matter if I turn the Master status back. HMI is not recognizing any data from PLC after such change. I would be very thankful could give me some advice.
The question is about redundant PLC (Siemens S400). Using manual I've configured them as you can see in attached picture. Selected S7 ISO TCP/IP protocol. In tag list connected them to different address (example:
0:DB30.DBX0.4
1:DB30.DBX0.4
to read the PLC status (Master or Stand by) . When the HMI panel (T15BR) start up, system read all data correctly, but when I switch over PLC, HMI don't update tag status, no matter which PLC is master and no matter if I turn the Master status back. HMI is not recognizing any data from PLC after such change. I would be very thankful could give me some advice.