SEW Motor's parameter for ACOPOS

Hi Community,
I’m trying to hookup SEW motor with ACOPOS but I can’t find few of parameters.
Could anyone help me about missing parameter?

Below for Motor nameplate.

And this is what I filled in for now and missing parameters.

Thank you

Hello Naronglit,

In general, the parameters for the motor should come from the motor manufacturer. These are physical/electrical characteristics of their device, of which they are the experts.

Of the boxed parameters, here’s some guidance.

Thermo sensor parameters. The temperature reporting system of the motor. This is a physical/device characteristic of the motor. If this information isn’t listed in the motor’s data sheet, you need to contact the manufacturer of the motor.
You could (temporarily) disable the temperature sensor to run the motor. I don’t recommend operating the motor without a temperature sensor, as you can damage the motor.

Voltage constant. This value is required to operate the motor. You need to get this from the motor manufacturer. If they don’t list it explicitly within the technical data of the motor, you can request it based on the description located in the B&R Help (ex. 8LSA motors). Pay attention to the units (V/1000 RPM or mV/RPM is the same).

Voltage constant (Ke)
V/1000 rpm
The voltage constant specifies the RMS value (phase-phase) of the reverse voltage induced by the motor at a speed of 1000 rpm (EMF). This value applies at a motor temperature of 20°C. When the temperature increases, the voltage constant is reduced (usually down to 5%). If the current increases, the voltage constant is reduced (typically starting at twice the value of the nominal current).

AS Help Link: General Motor Data, 8LSA - B&R Online Help (

Winding cross section. This is used in the thermal model the drive uses to predict the temperature within the motor (knowing that actual sensors have lag/error vs internal temps). I believe you can operate with this parameter ignored or guessed, but it’s best to get it from the motor manufacturer to best fit the model to the temperature of the motor.

Commutation offset. This is the radian offset between the encoder 0 point and electrical 0 for the voltage phases to control the motor. The offset can vary from individual motor to motor, depending on how careful the manufacturer is in setting the encoder. For non-B&R motors, this is usually measured on commissioning/startup by the Phasing routine. You don’t need to enter this value into the parameter table initially, but you will need to take account of it during commissioning/startup.
See: Phasing - B&R Online Help (



Hi Austin,
Thanks a lot for all information.
Now I stuck ant lag/error and temperature alarm that might caused by missing Winding cross section parameter.
I’m trying to get those parameters from SEW.
Once I’ve got the parameter will sharing the result again.

Now I stuck ant lag/error and temperature alarm that might caused by missing Winding cross section parameter.

  • Winding cross section isn’t mandatory. If you set it to zero you’ll on the safe side
  • for a short test you can deactive temperature sensor (be careful then)
  • lag error without a real load can be caused by inverted motor/encoder rotation.
    In this case you should see a fast increasing motor current / overcurrent message.
    But the phasing procedure for determining the commuation offset should detect this.
1 Like