How can I use a SCADA to monitor the Run or Stop state of a Unity Quantum PLC?

Issue:
How to use a SCADA to monitor the Run or Stop state of a Unity Quantum PLC

Product Line:
Unity Pro, Quantum

Resolution:
The Unity Quantum PLCs have a system bit, %S12 that will indicate the Run or Stop condition of the PLC. Unfortunately most SCADA packages can not access this bit. You can not use logic to move the system bit to a %M or %MW location because the logic will not be solved when the PLC is stopped. A common solution is to program a timer that continually runs and locate the ET (elapsed time) to a Memory word that can be monitored VIA the SCADA. At the SCADA, you can configure to alarm if the value stops changing.