ABB ACSM1 Manual page 160

160
25.04 DEC TIME
Defines the deceleration time, ie, the time required for the speed to change from the speed value
defined by parameter
If the speed reference decreases slower than the set deceleration rate, the motor speed will follow the
reference signal.
If the reference changes faster than the set deceleration rate, the motor speed will follow the
deceleration rate.
If the deceleration time is set too short, the drive will automatically prolong the deceleration in order
not to exceed drive torque limits. If there is any doubt about the deceleration time being too short,
ensure that the DC overvoltage control is on (parameter
Note: If a short deceleration time is needed for a high inertia application, the drive should be equipped
with an electric braking option, eg, with a braking chopper (built-in) and a braking resistor.
0...1800 s
25.05 SHAPE TIME ACC1
Selects the shape of the acceleration ramp at the beginning of the acceleration.
0.00 s: Linear ramp. Suitable for steady acceleration or deceleration and for slow ramps.
0.01...1000.00 s: S-curve ramp. S-curve ramps are ideal for conveyor and lifting applications. The S-
curve consists of symmetrical curves at both ends of the ramp and a linear part in between.
Note: When jogging or emergency ramp stop is active, acceleration and deceleration shape times are
forced to zero.
Speed
Linear ramp:
Par.
0...1000 s
25.06 SHAPE TIME ACC2
Selects the shape of the acceleration ramp at the end of the acceleration. See parameter
SHAPE TIME
0...1000 s
25.07 SHAPE TIME DEC1
Selects the shape of the deceleration ramp at the beginning of the deceleration. See parameter
SHAPE TIME
0...1000 s
Parameters and firmware blocks
FW block:
25.02 SPEED SCALING
Deceleration time.
FW block:
Linear ramp:
Par. 25.06 = 0 s
25.05 = 0 s
S-curve ramp:
Par. 25.06
S-curve ramp:
Par. 25.05
Ramp shape at beginning of acceleration.
FW block:
ACC1.
Ramp shape at end of acceleration.
FW block:
ACC1.
Ramp shape at beginning of deceleration.
SPEED REF RAMP
to zero.
47.01 OVERVOLTAGE
SPEED REF RAMP
Speed
Linear ramp:
> 0 s Par. 25.07
Linear ramp:
> 0 s Par. 25.08
Time
SPEED REF RAMP
SPEED REF RAMP
(see above)
CTRL).
(see above)
S-curve ramp:
Par. 25.07 > 0 s
S-curve ramp:
= 0 s Par. 25.08
= 0 s
(see above)
(see above)
> 0 s
Time
25.05
25.05