Dc Magnetization - ABB ACS180 Firmware Manual

66 Program features
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DC magnetization

The drive has different magnetization functions for different phases of motor
start/rotation/stop: pre-magnetization, DC hold, post-magnetization and pre-heating
(motor heating).
Pre-magnetization
Pre-magnetization refers to DC magnetization of the motor before start. Depending
on the selected start mode (vector or scalar) pre-magnetization can be applied to
guarantee the highest possible breakaway torque, up to 200% of the nominal torque
of the motor. By adjusting the pre-magnetization time, it is possible to synchronize the
motor start and, for example, the release of a mechanical brake.
Settings and diagnostics
Parameters 21.01 Start mode
21.02 Magnetization time
Events: -
DC hold
The function makes it possible to lock the rotor at (near) zero speed in the middle of
normal operation. DC hold is activated by parameter 21.08. When both the reference
and motor speed drop below a certain level, the drive will stop generating sinusoidal
current and start to inject DC into the motor. The current is set by parameter 21.10.
When the reference exceeds parameter 21.09, normal drive operation continues.
Motor speed
Reference
21.09 DC hold speed
Settings and diagnostics
Parameters 21.08 DC current control
and 21.10 DC current reference
Events: -
(page 152), 21.19 Scalar start mode
(page 153).
(page 156),
(page 156).
(page 157) and
DC hold
21.09 DC hold speed
t
t
(page 156)