7 Replies Latest reply on Jan 16, 2018 4:47 PM by asinclair-2 RSS
    asinclair-2 Apprentice

    How do I get a ValueStream to record only changes in the state of one property but also record concurrent property values?

    My device collects state information - a single property value - and sends the collected data in bulk to the server when a connection is available. Each record has start time and end time and the state value that held during that period. When a state change occurs the device generates two records - one that indicates the when the previous state ended and one that indicates when the next state began. What I want is every time the state value changes from A to B I want all three values logged to the ValueStream.

    In Thingworx, then, I have an entity that is bound to the device, The entity has 3 properties: LastOEEStartTime, LastOEEEndTime and OEEState all marked IsLogged:true. I defined OEEState with aspect DataChange Value and the other two with DataChange:Never. I thought this would do it.


    The results of QueryPropertyHistory show that I am getting a record in the Value stream for every record the device is sending. Why is that?


    It seems that I am getting a new entry in the value stream every time the OEEState property is written to whether the value has changed or not. Is this what I should expect?