There are three types of internal tags (non-I/O tags):


  • Memory: This type is just an internal Stream Gateway variable that can be changed at runtime by manual user action or by script.
  • Simulation: This type is Stream Gateway variable that holds a simulated value that is generated by Stream Server. (e.g. Ramp, Random, Sequence ... etc)
  • Calculation: This type is a Stream Gateway variable that holds a result of a formula.


All three types of internal data sources are defined by default in any Stream Gateway application.



In our tutorial, we'll add a calculation tag. This tag's formula is converting PUMP1.RUNTIME from minutes to hours (Simply divide by 60).


1. From Tags, add a new tag with the following details:


  • Tag Name: PUMP1.RUNTIME_HR
  • Data Source: CACLULATION
  • Data Type: Real
  • Calculation (formula): VAL(PUMP1.RUNTIME) / 60