ABB ACSM1 Firmware Manual page 40

40
Note: The same parameter is used by the autophasing routine which always writes
its result to parameter
updated even if the user mode is not enabled (see parameter
PARAMS).
Several autophasing modes are available (see parameter
MODE).
The turning mode is recommended especially with case 1 (see the list above) as it is
the most robust and accurate method. In the turning mode, the motor shaft is turned
back and forward (±360/polepairs)° to determine the rotor position. In case 3 (open-
loop control), the shaft is turned only in one direction and the angle is smaller.
The standstill modes can be used if the motor cannot be turned (for example, when
the load is connected). As the characteristics of motors and loads differ, testing must
be done to find out the most suitable standstill mode.
The drive is capable of determining the rotor position when started to a running
motor in the open-loop or closed loop modes. In this situation, the setting of
parameter
The autophasing routine can fail and therefore it is recommended to perform the
autophasing routine several times and check the value of parameter
OFFSET
The autophasing fault can occur in a running motor if the estimated angle of the rotor
differs too much from the measured angle of the rotor. One reason for different
values in the estimated and measured angles is that there is a slip in the encoder
connection to the motor axle.
Another cause for the autophasing fault is a failed autophasing routine. In other
words, there has been a wrong value in parameter
the beginning.
The third reason for the autophasing fault in a running motor is that there is a wrong
motor type in the control program or that the motor ID run has failed.
In addition, fault
parameter
requires that the rotor can be turned during the autophasing routine. If the rotor is
locked or cannot be easily turned or if the rotor turns by force of external power, the
autophasing fault is triggered. Regardless of the chosen mode, the autophasing fault
occurs if the rotor is turning before the autophasing routine is started.
Drive control and features
97.20 POS OFFSET
11.07 AUTOPHASING MODE
USER.
0026 AUTOPHASING
11.07 AUTOPHASING MODE
USER. Autophasing ID run results are
11.07 AUTOPHASING
has no effect.
97.20 POS OFFSET USER
can occur during the autophasing routine if
is set to Turning. The Turning mode
97.01 USE GIVEN
97.20 POS
from