How is output KW measured in the ATV61 drive?

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Issue:
Output measured (KW) in the ATV61

Product Line:
ATV61 / ATV71

Environment:
All

Cause:
NA

Resolution:
The power of motor is not measured by the drive. It is calculated from the measurement of motor current and the output speed (estimated in open load and measured in closed loop).
OPR = (Iq / Iqn) * (Spd / Nn) * (PhirdRef / Phirn) in %
With: Iq : Current torque provide by the command to drive motor
PhirdRef : Flux provide by the command to drive motor
Iqn : Nominal Current torque compute with the motor name plate
Spd : Spd of the rotor, estimated or measured
Nn : Nominal speed of motor name plate
Phirn : Nominal flux of the motor

The accuracy of motor power is around 10%.