ABB ACS355 series, User Manual

Page: 138 / 436

138 Program features
Power loss ride-through
If the incoming supply voltage is cut off, the drive will continue to operate by utilizing
the kinetic energy of the rotating motor. The drive will be fully operational as long as
the motor rotates and generates energy to the drive. The drive can continue the
operation after the break if the main contactor remained closed.

Settings
Parameter 2006 UNDERVOLT CTRL
DC magnetizing
When DC magnetizing is activated, the drive automatically magnetizes the motor
before starting. This feature guarantees the highest possible break-away torque, up
to 180% of the motor nominal torque. By adjusting the premagnetizing time, it is
possible to synchronize the motor start and, eg, a mechanical brake release. The
Automatic start feature and DC magnetizing cannot be activated at the same time.

Settings
Parameters 2101 START FUNCTION and 2103 DC MAGN TIME
130
260
390
520
1.6 4.8 8 11.2 14.4
t (s)
U
DC
f
out
T
M
U
DC
= Intermediate circuit voltage of the drive, f
out
= Output frequency of the drive,
T
M
= Motor torque
Loss of supply voltage at nominal load ( f
out
= 40 Hz). The intermediate circuit DC voltage
drops to the minimum limit. The controller keeps the voltage steady as long as the input
power is switched off. The drive runs the motor in generator mode. The motor speed falls but
the drive is operational as long as the motor has enough kinetic energy.
U
input power
20
40
60
80
40
80
120
160
T
M
(N·m)
f
out
(Hz)
U
DC
(Vdc)
0 0 0