Speed Reference Generation; Other Control Blocks; Acs_Ctrl_Abb_Drv_Profile - ABB ACS355 Application Manual

26 Function blocks and program structure

Speed reference generation

In the example program, speed reference is generated according to the dip switches
(DI_FASTER, DI_SLOWER and DI_REVERS) and the maximum reference limit.
The maximum reference limit is read from the drive parameter 11.05 (REF1 MAX) at the
first start of the ACS3XX_DRIVES_CTRL_BASIC function block and is stored in
config.iRefScaleMax, a sub-element of the DriveRef variable.
The limit depends on the selected motor control mode. There are two possible motor
control modes, detailed below. Drive parameter 99.04 Motor Control Mode determines the
mode used.
•
Scalar mode: The default mode is the scalar mode. The default value for the drive
parameter REF1 MAX is 500 (which corresponds to 50 Hz).
•
Vector mode: In the vector mode, the drive paramter REF1 MAX is set to the
maximum speed given in rpm, eg 1500.
If you change the motor control mode, the scaling parameter has to be read again by
reseting EN of ACS3XX_DRIVES_CTRL_BASIC. This can be done by powering off and
on again the 24V DC of the AC500.
DI_FASTER, DI_SLOWER and DI_REVERS are used in the example project as shown in
the below image. See the quick installation guide for the dip switch settings in the ACS355
and AC500-eCo starter kit.

Other control blocks

You can use the following two control blocks as alternatives for the basic control block.

ACS_CTRL_ABB_DRV_PROFILE

If advanced control is needed, the
ACS_DRIVES_CTRL_STANDARD function block can be used
instead of the FB_BASIC_CONTROL function block. Refer to
the online help for a detailed description of the function block.