D-138
Parameter Reference
Functional Description
The feature needs to be run after each power cycle with a PMAC motor associated to a relative encoder type ( pulse encoder for example ).
The feature is run on a motor free to rotate, no load attached to the motor shaft.
Regardless of the Alignment Method selected, the motor should move during the sequence.
The sequence is validated by Alignment Enable input.
The drive waits for a START condition to start the cycle.
The sequence can be stopped by a STOP command anywhere during the cycle.
A successful sequence sets Alignment Ended = TRUE.
A TORQUE OFF command is needed to stop the sequence.
If Alignment Method is set to AUTOMATIC, it is possible that the direction of motor rotation for a positive setpoint could be reversed. The
parameter PMAC Wiring can be changed by the sequence if an incompatibility of direction between the encoder and the motor phases
wiring is found.
Alignment Method = MANUAL
The motor is moved to an electrical position corresponding to the motor phase selected by Alignment On Motor parameter.
This electrical position depends on the PMAC Wiring type selected and on the real motor phase wiring.
PMAC Encoder Offset is calculated by looking at real position from the active encoder compared to theoretical position where the motor is.
So, it depends also on the encoder settings ( inverted or not ).
For standard connections ( correct U, V, W motor wiring sequence and position from encoder varying in a positive way looking at the motor front
shaft ), position offset is extracted and written back into PMAC Encoder Offset.
Correct connection of the encoder means that a clockwise rotation of the motor front shaft equals a positive position variation.
Correct motor wiring means phase U, V, W rotating in a correct sequence for a clock wise rotation of the motor front shaft.
Considering a standard connection, the following table gives possible encoder and PMAC Wiring settings and results on speed control :
1809 PMAC Wiring
STANDARD
STANDARD
REVERSE
REVERSE
*
Active Encoder Invert refers to the active speed feedback invert parameter.
**
Looking the front shaft of the motor
***
The motor is uncontrolled. It could overspeed, be stalled, or running at constant speed without any control.
Active Encoder Invert*
FALSE
TRUE
FALSE
TRUE
Correct speed control
YES
Clockwise direction
NO***
NO***
YES
Counter clockwise direction
Positive Speed setpoint **
AC30 series Variable Speed Drive