You are currently viewing the content available in Vietnam. If you are looking for information for another region, please select the correct country from the top-left dropdown in the page and 'Navigate to Browse FAQs' in the Support menu.
Issue:
Customer needs to know the formula by which motor torque is calculated in order to program some custom function blocks for their application.
Product Line:
ATV320 series drives.
Environment:
All models, all serial numbers.
Cause:
Information this detailed is not available in the programming or installation manuals.
Resolution:
Customer needs to know the formula by which motor torque is calculated in order to program some custom function blocks for their application.
Product Line:
ATV320 series drives.
Environment:
All models, all serial numbers.
Cause:
Information this detailed is not available in the programming or installation manuals.
Resolution:
OTR and SOTR represent the motor torque. OTR is filtered value and SOTR is unfiltered value. The scaling is also different between OTR and SOTR. This difference, one value with filter and the other one without filter explain the big difference between the maximum value of OTR and SOTR. SOTR will represent the instantaneous torque, compare to OTR that will add filter before display. SOTR represent the real motor torque and OTR is more here to show the value on a display. Concerning the range, OTR is expressed in % of nominal motor torque with 100% = Nominal motor torque. OTR value is signed with minimum value -300% and maximum value 300% OTR and SOTR (the torque) are estimated based on motor current measured. The torque of motor 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 This is for OTR. SOTR use the same data, but concerning the range, SOTR is expressed without unit and scaled on 12bits. SOTR value is signed with minimum value -32767 and maximum value 32767 Like there is no unit on SOTR compare to OTR, the both value will be different. Example within Red OTR and in Blue SOTR OTR show 32.3% and SOTR show 130.5% The relation is: SOTR = OTR x 4,096 In this example: SOTR = 32,3 * 4,096 = 132,3 (close to the 130.5 if we take into account the oscillation on the SOTR because of no filter). |