ABB ACSM1 - Page 128

Parameters and firmware blocks
128
11.06 DC HOLD FW block: START/STOP MODE (see above)
Enables the DC hold function. The function makes it possible to lock the rotor at zero speed.
When both the reference and the speed drop below the value of parameter 11.04 DC HOLD SPEED,
the drive will stop generating sinusoidal current and start to inject DC into the motor. The current is set
by parameter 11.05 DC HOLD CUR REF. When the reference speed exceeds parameter 11.04 DC
HOLD SPEED, normal drive operation continues.
Notes:
• The DC hold function has no effect if the start signal is switched off.
• The DC hold function can only be activated in speed control mode.
• The DC hold function cannot be activated if par. 99.05 MOTOR CTRL MODE is set to (1) Scalar.
• Injecting DC current into the motor causes the motor to heat up. In applications where long DC hold
times are required, externally ventilated motors should be used. If the DC hold period is long, the
DC hold cannot prevent the motor shaft from rotating if a constant load is applied to the motor.
Bit pointer: Group and index and bit
(0) Disabled DC hold function disabled.
(1) Enabled DC hold function enabled.
11.07 AUTOPHASING MODE FW block: START/STOP MODE (see above)
Selects the way the autophasing routine is performed. See also section Autophasing on page 42.
(0) Turning This mode gives the most accurate autophasing result. This mode can
be used, and is recommended if it is allowed for the motor to rotate
and the start-up is not time-critical. Note: This mode will cause the
motor to rotate during the motor ID run.
(1) Standstill 1 Faster than the (0) Turning mode, but not as accurate. The motor will
not rotate.
(2) Standstill 2 An alternative standstill autophasing mode that can be used if the
TURNING mode cannot be used, and the (1) Standstill 1 mode gives
erratic results. However, this mode is considerably slower than (1)
Standstill 1.
t
t
DC Hold
Motor speed
Reference
11.04 DC HOLD SPEED