Patent ID: 8714934

Claim:
Circulation pump for a conveyed liquid, comprising: an electric motor, which is electronically commutated and has a rotor, a stator and a motor circuit; and an impeller that is connected in a rotationally fixed manner to the rotor; the motor circuit comprising an evaluation device, by means of which a flow rate of conveyed liquid through the circulation pump is determinable from at least one of a rotational speed of the rotor and a power consumption of the electric motor, and at least one external signal output, by which at least one of a flow rate signal and flow rate-dependent switching signal is suppliable out of the circulation pump, wherein: the motor circuit comprises means for providing an operating mode with at least one of control to a constant motor power and control to a constant rotational speed, in the operating mode with the control to a constant motor power, the evaluating device is adapted to determine the flow rate with given defined motor power from the rotational speed, and in the operating mode with the control to a constant rotational speed, the evaluating device is adapted to determine the flow rate with given rotational speed from power consumption data provided by the motor circuit.