I am using Ac500 cpu PM590v1.2 on two redundant systems (groups). I am using ethernet port on CPU for redendancy and CM577 for SCADA and Modbus communication.
The runtime conditions in Standby PLC in one group are not identical with Master PLC.
Can anybody tell me how can I syncrinize two PLCs in a redendant group?
In second group, Master PLC does not allow to write any data from SCADA but if I make this PLC unavailable and allow to Standby to take over, Standby PLC can read and write data to SCADA. I do not understand why Master PLC do not allow to write eventhough PLC program is same.
Also I want to share data between these two groups on Modbus.
For e.g Two PLCs from each group should write data to Two PLCs in other group but Each PLC can accept the data only from one PLC from other group which is Master.
Can anybody help me on this?
Thanks in advacne.
Regards,
Ashish
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Hello All,
I am using Ac500 cpu PM590v1.2 on two redundant systems (groups). I am using ethernet port on CPU for redendancy and CM577 for SCADA and Modbus communication.
The runtime conditions in Standby PLC in one group are not identical with Master PLC.
Can anybody tell me how can I syncrinize two PLCs in a redendant group?
In second group, Master PLC does not allow to write any data from SCADA but if I make this PLC unavailable and allow to Standby to take over, Standby PLC can read and write data to SCADA. I do not understand why Master PLC do not allow to write eventhough PLC program is same.
Also I want to share data between these two groups on Modbus.
For e.g Two PLCs from each group should write data to Two PLCs in other group but Each PLC can accept the data only from one PLC from other group which is Master.
Can anybody help me on this?
Thanks in advacne.
Regards,
Ashish