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How is the Otr motor torque parameter calculated on the ATV61 and ATV71 drives?

Issue:
How is the Otr motor torque parameter calculated on the ATV61 and ATV71 drives?

Product Line:
Altivar ATV61 and ATV71

Environment:
All

Cause:
Needs to know how the motor torque Otr parameter is calculated

Resolution
The torque of motor (OTR) is not measured by the drive. It is calculated from the measurement of motor current.
OTR = (Iq / Iqn) * (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
                    Phirn : Nominal flux of the motor
The maximum accuracy of motor torque is 5% (in closed loop). It can be up to 15% in open loop.

Concerning the range, OTR is expressed in % of nominal motor torque.
100% = Nominal motor torque.
OTR value is signed with minimum value -300% and maximum value 300% 
 
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