godfrey
Member
I have a few questions about how SCADA and a PLC share data. For example, when a SCADA sends a setpoint value to the PLC, does it send only once or does it continue to brodcast the setpoint. As an example, say an integer setpoint is sent via SCADA to a PID loop. Let's say the value is 400 gpm. On the OIT which is connected to the PLC, the same setpoint can be entered. If a value of 300 gpm is sent via the OIT, it just sends the data to the PLC register once. Will the SCADA overwrite it to 400 or will it remain at 300?
How about bits? If a pushbutton on the OIT is set up as maintained, can the SCADA change the state of the PLC bit which the OIT addresses?
These questions are geared toward Wonderware and Intellution systems and SLC 500 PLCs but not to any particular project.
How about bits? If a pushbutton on the OIT is set up as maintained, can the SCADA change the state of the PLC bit which the OIT addresses?
These questions are geared toward Wonderware and Intellution systems and SLC 500 PLCs but not to any particular project.