In short: The point at which a pump will operate in an installation. It will occur at the intersection of the pump H-Q-curve and the installation HA-Q-curve.
The operating point of a pump is the point in the characteristics chart of a pump where the pump characteristic and installation characteristic intersect. At this point, the output range of the pump and the power consumption in the piping system are balanced. The operating point describes the point at which the pump operates with the lowest losses and the highest efficiency. This makes it an important basis for the decision on how to dimension the pump.
Since the operating point is not fixed, but can change depending on the flow rate, the maximum requirements on the pump in operation must be taken for dimensioning. In the characteristics chart, all operating points that occur during ongoing operation fall to the left of this maximum operating point.
The speed control enables operating the pump close to the operating point, and adjusting head and flow rate depending on the demand. This makes it possible to lower the operating costs of the installation.