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Why do I see extra time steps inserted between main timesteps, per the hydraulic timestep?Why do I sometimes see intermediate timesteps in my results, and how can I ignore them?
For example the hydraulic timestep is set to 1.0 hours, but results are reported at 1.10 hours.
In an EPS simulation, WaterCAD and WaterGEMS will insert intermediate timesteps, up to one tenth of a hydraulic timestep. Meaning, it will add additional timesteps between the step defined in your calculations.This happens when the program determines that a tank will fill or drain or if a logical control will trigger before the next scheduled timestep (per the calculation options). This is done for better accuracy. Click on the timestep in question in the Calculation Summary, then click the Information and Status Messages tabs to see what tanks or controls are causing it.If you'd prefer to not see these additional time steps, you can choose "Constant" for the "Reporting Timestep" calculation option and set the reporting timestep equal to the hydraulic time step.Note that excessive intermediate timesteps are often an indicator of problems with tanks and/or controls. For example a tank may be hovering near 100% or 0% full (a graph of all tanks can determine this), which initiates a built in altitude valve that may be closing an opening. Check to make sure your controls are reasonable and that they are configured such that tanks do not become full or empty.
Rapid flow oscillation between hydraulically close tanks