Hello,
I have 2 tags on my PI system that calculate the start time and stop time of a machine. I use further these tags to make an automatic Excel report that is triggered from FT View SE (Rockwell). My problem is that sometimes the PI system doesn't calculate the new value for the tags. The two tags are made as:
Coloana_D_time_start (type timestamp) : Event=RSLINX:RSLinx Enterprise:PLC.status_col_D, if tagval('RSLINX:RSLinx Enterprise:PLC.status_col_D','*') = "ON" and PrevVal('RSLINX:RSLinx Enterprise:PLC.status_col_D',PrevEvent('RSLINX:RSLinx Enterprise:PLC.status_col_D')) = "OFF" then '*' else 'Coloana_D_time_start'
Coloana_D_time_stop (type timestamp):Event=RSLINX:RSLinx Enterprise:PLC.status_col_D, if tagval('RSLINX:RSLinx Enterprise:PLC.status_col_D','*') = "OFF" and PrevVal('RSLINX:RSLinx Enterprise:PLC.status_col_D',PrevEvent('RSLINX:RSLinx Enterprise:PLC.status_col_D')) = "ON" then '*' else 'Coloana_D_time_stop'
The triggering event ('RSLINX:RSLinx Enterprise:PLC.status_col_D) is a boolean tag connected to a PLC via FTLD Interface.
Sometimes the calculation doesnt work for falling edge of the boolean tag as you can see in the ProcessBook trend (follow purple color). What can be the problem? If you need extra info for the tags I can provide. Maybe there is an easier way to accomplish this goal?
