Status Bar

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Navigation: User Guide ➔ Status Bar

This is shown on the bottom of the main SysCAD window. It is divided into a number of sections. The large section (Left-hand side) is used to display SysCAD status, commands or FlyBys. (See General Options Toolbars)

The area on the right is shown here:

SysCAD in Edit Mode:

Running in Steady State:


Running Dynamic Simulation:

Button Small 1.png displays the active window, in this case the Graphics Window.
Button Small 2.png displays different information depending on the current operation.
  • if SysCAD is stopped and the mouse cursor is pointed on a Graphics Window, the number displayed is the position of the pointer.
  • if SysCAD is running a Steady State simulation, it shows the number of iterations executed and time taken. For example "70/0:01.898" means the simulation has gone through 70 iterations and spent 1.898 seconds so far to solve the model. These values correspond to tags PlantModel.Stats.Iterations and PlantModel.Stats.SolveTime.
  • if SysCAD is running a dynamic simulation, the number shown will represent the time span for which this project has been simulated.
Button Small 3.png Display different information depending on SysCAD solver mode.
  • Steady State simulation: Shows the maximum error for convergence. This correspond to the value shown in Solver Status window. When the Max Error value is < 1.0 all the Criteria are considered converged (model is "solved"). The number of significant digits is based on the global relative tolerance specified. This value corresponds to tag $Solver.Convergence.Error.[Worst].Max.
  • Dynamic Simulation: Shows the step size.
Button Small 4.png Display different information depending on SysCAD solver mode.
  • Steady State simulation: Shows Number of criteria solved. For example "7 of 10" means 7 of the 10 criteria for convergence have been met. These values correspond to Solver Setting - Convergence tags $Solver.Convergence.Criteria.Active and $Solver.Convergence.Criteria.Done.
  • Dynamic Simulation: There are three possible displays: S (steps), I (iterations) and B (Bad Step). These values correspond to Solver Setting - Convergence tags $Solver.Convergence.Steps, $Solver.Convergence.Iterations and $Solver.Convergence.Steps.Bad. See comments below for further information.
Button Small 5.png Display the SysCAD State. See Plant Model - States - AppState and AppState.Detail for full list of states. These states are also available as special tags for OPC.
Button Small 6.png If script commands are currently being executed, an additional pane showing the number of script commands to be executed will be shown.

Dynamic Status Bar Display Information and Comments

In Dynamic, each time step may have 1 or more iterations to converge recycles for that time step. The term "I" (Iterations) is only displayed in status bar if more than 1 iteration is required.

When S(Step)=1 and I(Iteration)=1 your model is running at the fastest possible speed (only one iteration for each time step). It is OK to have a number of iterations, especially when a step change occurs.

You can set a maximum number of iterations per step. At any time when step hits the Iteration limit, then the B (bad step) counter increments. The mass balance “error” is stored in the tear. SysCAD does try to clear this “stored mass error” in subsequent time steps.

Examples of possible display on the status bar:

  • Shows the number of steps executed: "S:52".
  • If at any time a step did not converge, an additional count of "Bad step" is given. For example "S:52 B:2" means that 2 of the 52 steps did not converge within the maximum number of allowed iterations.
  • If more than one iteration is required to converge recycles within the current time step, then a count of the number of iterations for this step is shown. "S:52 (I:7)" or "S:52 B:2 (I:20)"

Ideally, we do not want any “Bad” steps and would want to minimise the number of iterations per step.

To troubleshoot bad steps, try reviewing the following in the project:

  • step size (time)
  • recycles - in particular check if any surge and/or “overflow tanks” in the recycle (these provide significant damping and stability).
  • Control logic (especially for events / step changes)
  • Review initial conditions (for startup)