Dc Hold; Settings; Speed Compensated Stop; Flux Braking - ABB ACS350 User Manual

108

DC Hold

By activating the motor DC Hold feature it is possible to
lock the rotor at zero speed. When both the reference
and the motor speed fall below the preset DC hold
speed, the drive stops the motor and starts to inject DC
into the motor. When the reference speed again exceeds
the DC hold speed, the normal drive operation resumes.

Settings

Parameters

Speed compensated stop

Speed compensation stop is available e.g.
for applications, where a conveyer needs to
travel a certain distance after receiving the
stop command. At maximum speed the
motor is stopped normally along the defined
deceleration ramp. Below maximum speed
stop is delayed by running the drive at
current speed before the motor is ramped to
a stop. As shown in the following figure, the
distance travelled after the stop command is the same in both cases, i.e. area A
equals area B.
Speed compensation can be restricted to forward or reverse rotating direction.
Settings
Parameter

Flux Braking

The drive can provide greater deceleration by raising the level of magnetisation in
the motor. By increasing the motor flux, the energy generated by the motor during
braking can be converted to motor thermal energy.
Motor
speed
Program features
2104...2106
2102 STOP FUNCTION
No Flux Braking
Flux Braking
Speed
Max. speed
Used speed
T
Br
(%)
T
N
60
40
Flux Braking
20
No Flux Braking
t (s)
Motor
speed
DC Hold
DC hold
speed
Speed
reference
DC hold
speed
Stop command
area A = area B
T = Braking torque
Br
T = 100 N·m
N
f (Hz)
50 Hz / 60 Hz
t
t
A
B
t