Write Boolean Value to PLC connect from ABB800xA SCADA
Hi,
I wanted to transfer Start/Stop command from ABB 800xA scada to Boolean tags in PLC connect but I am not able to write anything to Boolean tag in PLC connect. I am able to read all tags and values in ABB800xA from PLC connect fine. I have Enabled "IS Controllable" check box for those tags under singal configuration but still not able to write any values to PLC connect tags from HMI. I may have to do something with Property transfer definition but I am not fully sure therefore I haven't configured property transfer definition.
The Start/Stop command from ABB800xA HMI should be latched and 3rd party PLC will unlatch the command once the command is processed. Can someone please also guide me on how can I configured Push Button which stays latched once I pushed it and only unlatches when It gets reset from 3rd party PLC.
I am using ABB800xA version 5.1.
Thank you.
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Property Transfer is not part of PLC Connect. The HMI screens should work without Property Transfer.
*ALL* writes by the HMI to the PLC using an OPC server are "one shot". The HMI only ever writes once. This is an OPC thing not an ABB thing. All HMI's work this way. So if you write "1" to a PLC memory location it stays there until the PLC overwrites it or the HMI resets it. The "latching" you are asking for is an in-built feature of every OPC server - you dont have to do anything special.
To show the state of the command you just wrote, read back the command and display it on the HMI. So if you are using a ToggleButton element for example, then you simply display the value of the command. The toggle button will also detect if the PLC switches off the command.
When you say " I am able to read all tags and values in ABB800xA from PLC connect fine" are you displaying these live values on a graphic ? Looking at them in plant explorer ? Using a third party OPC client to read the data ?
Most likely you are not writing to the correct OPC property.
Answers
I think I didn't explain well in my previosus question, apologies for that.
Can you please let me know if i need to do anything apart from enable "IS Controllable" check box under particular tag under PLC connect to write data to it from ABB800xA SCADA or control structure?
I am able to read all data from PLC connect and displaying that on Graphics in ABB800xA but in this instance I want to write to PLC connect boolean tag from ABB800xA, Can you please guide me on how I can achieve this?
I have checked 3rd party OPC property and thats set to "RW" access which makes me think I should be able to write to that tag from ABB800xA.
Thank you.
-/nimeshvora
Hi Rob, Thank yo so much for your help. I manage to resolve the issue without using property definition transfer aspect. You were correct that "IS Controllable" checkbox enable is enougg to write data to PLC Net from ABB800xA Scada. The issue was with with OPC permission thogh it was showing "RW", it wasnt accepting data from ABB 800xA, I had to reconfigured OPC server for the PLC then it allowed me to write data from ABB800xA.
Regarding latched push button from ABB800xA Scada, I used normal button with "Direct" function which write value to OPC then OPC is retaining the value though push button has been reset automatically by ABB800xA which is I was looking for.
Thank you so much for your help, its really appreciated.
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