When computing the transient simulation or using the Validate command in HAMMER, the following red notification appears, preventing calculation:
"Pump Efficiency must be between 0% and 100% inclusive."However, the pump efficiency is between 0% and 100%.
"Combined pump and motor efficiency should be between 30% and 95% inclusive."
The transient solver in HAMMER assumes that a pump is operating at or near the best efficiency point. Otherwise, transient results can be skewed because of the way that the initial head and flow are used to construct a four-quadrant representation of the pump. The efficiency of a pump is different depending on the operating point. Go to Components > Pump Definitions, click your pump definition and look at the plotted efficiency for each operating point. In the properties of the pump element in question, look at the pump head and flow and compare that operating point with the pump curve to see what the efficiency is. You can also right click on the pump, choose the Pump Curve option and check the box for "efficiency".
Here are some possible causes and solutions:
WaterGEMS/WaterCAD user notification: "Network Unbalanced"
What is the best way of modeling the best efficiency point (BEP) when modeling a pump in HAMMER?
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