Method

No method

The display element of the inverter shows 18.

FCB 18 is active but the rotor position is only determined if the parameter Use fixed offset memory is set to 1 (Yes).

With rotating motor

The rotor position is determined while the motor is rotating. The motor must be able to rotate freely (without load).

To determine the rotor position, the motor is rotated clockwise for one revolution and then back to the starting position.

SEW‑EURODRIVE recommends using this method for all motor types.

With stopped motor – hi-res

The rotor position is determined while the motor is at standstill.

This method can only be used for certain motors of SEW-EURODRIVE whose particular physical properties have already been determined by SEW-EURODRIVE.

With stopped motor – lo-res

The rotor position is determined while the motor is at standstill. The motor must already have been measured with the FCB 25 Motor parameter measurement drive function.

For technical reasons, this method is less accurate than the other 2 methods: It is possible that more current flows for the same torque.

SEW-EURODRIVE recommends using this method in exceptional cases only (motor cannot be separated from the load).