Inlet cross-section
The pump's inlet cross-section is usually deemed to be the flow cross-section of the pump suction nozzle. If there is no suction nozzle the inlet cross-section must be defined as a suction-side flow cross-section (e.g. of a tank, a pipe) with known geodetic and hydraulic data (see NPSH). Refer to DIN EN ISO 17769-1 for examples.