ABB ACSM1 - Operating Modes of the Drive; Speed Control Mode; Torque Control Mode

Drive control and features
36
Local control is mainly used during commissioning and maintenance. The control
panel always overrides the external control signal sources when used in local
control. Changing the control location to local can be disabled by parameter 16.01
LOCAL LOCK.
The user can select by a parameter (46.03 LOCAL CTRL LOSS) how the drive
reacts to a control panel or PC tool communication break.
External control
When the drive is in external control, control commands (start/stop, reset etc.) are
given through the fieldbus interface (via an optional fieldbus adapter module), the I/O
terminals (digital inputs), optional I/O extension modules or the drive-to-drive link.
Two external control locations, EXT1 and EXT2, are available. The user can select
control signals (eg, Group 10 START/STOP, Group 24 SPEED REF MOD and
Group 32 TORQUE REFERENCE) and control modes (Group 34 REFERENCE
CTRL) for both external control locations. Depending on the user selection, either
EXT1 or EXT2 is active at a time. Selection between EXT1/EXT2 is done via a freely
selectable bit pointer parameter 34.01 EXT1/EXT2 SEL. In addition, the EXT1
control location is divided into two parts, EXT1 CTRL MODE1 and EXT1 CTRL
MODE2. Both use the EXT1 control signals for start/stop, but the control mode can
be different; for example, EXT1 CTRL MODE2 can be used in homing.
Operating modes of the drive
The drive can operate in speed and torque control modes as well as position,
synchron, homing and profile velocity modes. Block diagrams of the control chain for
speed and torque control as well as positioning are presented on page 40; more
detailed diagrams are presented in Appendix E – Control chain and drive logic
diagrams (page 501).
Speed control mode
Motor rotates at a speed proportional to the speed reference given to the drive. This
mode can be used either with estimated speed used as feedback, or with an
encoder or resolver for better speed accuracy.
Speed control mode is available in both local and external control.
Torque control mode
Motor torque is proportional to the torque reference given to the drive. This mode
can be used either with estimated speed used as feedback, or with an encoder or
resolver for more accurate and dynamic motor control.
Torque control mode is available in both local and external control.