14.7 Frequency ramps
The ramps determine how quickly the frequency value is changed if the reference
value changes or after a start, stop or brake command. The maximum admis
ramp gradient can be selected according to the application and the current con-
sumption of the motor.
If the settings of the frequency ramps are identical for both directions of rotation, the
parameterization via the parameters Acceleration (clockwise) 420 and Deceleration
(clockwise)
421 is sufficient. The values of the frequency ramps
Acceleration anticlockwise 422 and Deceleration anticlockwise 423
been parameterized to the factory setting of -0.01 Hz/s.
The parameter value of 0.00 Hz/s for the acceleration blocks the corresponding di-
Acceleration anticlockwise
Deceleration anticlockwise
1)
Value -0.01 Hz/s means: Acceleration (Clockwise) 420 is applied.
2)
Value -0.01 Hz/s means: Deceleration (Clockwise) 421 is applied.
The setting 0.00 Hz/s won’t accelerate or decelerate the drive due to the limitation of
the ramp.
The ramps for the Emergency stop clockwise 424 and Emergency stop anticlockwise
425 of the drive mechanism to be activated via Operation mode 630 for the stop-
ping behavior must be selected according to the application. The non-linear (S-
shaped) course of the ramps is not active in the case of an emer
424 Emergency stop clockwise 0.01 Hz/s 9999.99 Hz/s 5.00 Hz/s
425 Emergency stop anti-clockwise 0.01 Hz/s 9999.99 Hz/s 5.00 Hz/s
Rotary field
clockwise
Rotary field
anticlockwise
+f
m ax
-f
ma x
t
Acceleration
(Clockwise)420
Deceleration (Clockwise)
Emergency Stop
or
421
424Clockwise
Acceleration
anticlockwise() 422
Deceleration anticlockwise
Emergency Stop anticlockwise
or
423
425
06/13 Operating Instructions ACU 163