A Warning message in AFT Fathom

Centrifugal pump curves typically have a point at which they no longer operate on the curve. This may be called "end of curve" or "runout". Data defining runout for a particular pump is given by the manufacturer. Such data has been defined for this pump in the Pump Configuration window Configuration Data tab, and the system is operating past the runout flow rate. Thus the results are invalid, because the pump likely cannot actually operate at that point.