4 Replies Latest reply on Mar 12, 2014 1:22 PM by mhamel

    Explaination error status on tag's value


      Hello, can anyone confirm the field already filled and suggest me how complete the table below?



      Error Status Description
      AccessDenied Access Denied status events are written whenever the interface is denied access to a tag’s data or attribute information.
      Bad Data  
      Bad Quality  
      Comm Fail  
      DCS failed  
      Equip Fail  
      I/O Timeout Interfaces use this state to indicate that communication with a remote device has failed.
      Intf Shut Intf Shut status events are enabled through /stopstat startup parameter. When enabled an event is written when the interface is stopped and again on startup. These events tell users no data is being collected because the interface is not running.  
      Invalid Data  
      No Data Data-retrieval functions use this state for time periods where no archive values for a tag can exist 10 minutes into the future or before the oldest mounted archive
      Not Connect  
      Out of Serv  
      Pt Created This state is assigned to a tag when it is created. This is a tag's value before any value is entered into the system.
      Scan Off If any PI point is removed from the interface while the interface is running (including setting the scan attribute to 0), SCAN OFF will be written to the PI point regardless of the value of the Scan attribute
      Scan Timeout  
      Shutdown All tags that are configured to receive shutdown events are set to this state on system shutdown.
      Unit Down  

       Thanks for help,







          • Re: Explaination error status on tag's value

            @Marco: Regarding the definitions of error statuses that you put already, they are accurate and quite easy to understand.


            Bad: This is the equivalent to Bad Data and was used with older interface. Some interface plug-ins are using it to report bad calculations or empty lookup results.


            Bad Data: Device, Interface or application use this state to identify that a tag's data is of uncertain quality or that engineering units were exceeded. The reasons to obtain an uncertain quality are multiple.


            Bad Quality: This state is assigned when the value returned is sub-normal.


            Comm Fail: This state is assigned by the data source when communication is not or no longer possible with the device.


            Configure: The tag configuration has been rejected as invalid by the data source, check the interface message logs for additional information.


            DCS failed: Interfaces use this state to indicate that all tags in a scan class are affected by a DCS API call that fails.


            Equip Fail: This state is assigned by the DCS or PLC when a sensor is failing. Failed: This is assigned by the interface to report a general failure during input or output for a given tag.




            I hope this helps!

            2 of 2 people found this helpful
              • Re: Explaination error status on tag's value

                Thanks Mathieu, your post was a great help to me!


                On OPC's manual i have found a matching beetween tags' error on PI and error on OPC Server, and on the web i have found the desciptions for this errors. For other type of interfaces (OPCHDA, UFL, XML, PITOPI, DNP3, RDBMSPI), i have seen the manuals, but i can't found something like the mapping for OPC. Can you sugget me where I can find a list of error for any type of interfaces, and eventually (if exist) the mapping beetween errror on PI and error for interface?

                  • Re: Explaination error status on tag's value

                    @Marco: Most of my answers are coming from different sources such as our KB articles, PI Interface manuals and OPC standards. I cannot point you one in particular and say that use this one exclusively. Don't forget that these System Digital States are configured to cover all possibilities from different systems (DCS, SCADA, PLC, custom applications, etc.), it would then be difficult to have one manual to cover them all. Although, maybe this is a good suggestion (enhancement request) for creating an appendix in the PI Server Reference/PI AF Server guide to cover all definitions of digital states. I suggest that you send it to our Technical Support department so they can open a ticket for this matter. To understand the OPC quality values, please click here and download the OPC Data Access specifications, which contain a brief discussion of quality data. The OPC quality table can also be found in the PI OPCClient User’s Guide too.


                    I hope this helps!

                    1 of 1 people found this helpful