Baumuller b maXX BM2500, Operating Manual

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Description of the Software Modules and Parameters
Parameter manual b maXX BM3000
Document no.: 5.12001.07
399
of 820
4
4.6 Set Value Generators
4.6.1 Ramp function generator
The ramp function generator is used to generate rising or falling ramps in the Speed Pre-
set 1 (
Z
109.1
–
= 2) and Speed Control (
Z
109.1
–
= -3) speed-controlled operating
modes. Additionally, it is used for controlling braking procedures (Quick Stop, Drive Shut-
down, Inhibit Drive).
The ramp function generator has an input with separately adjustable ramp-up and ramp-
down times. Furthermore the ramp-down time for the Quick Stop function is separately
adjustable.
The input and output values for the ramp function generator are relative quantities
(±100 %) and are referred to the Maximum drive speed parameter (
Z
110.13
–
).
The ramp slope for the acceleration and braking procedures is defined by the ramp-up
and ramp-down times. The times correspond to a 100 % change in the set value.
For additional rounding of the ramp-up or ramp-down ramps, a PT
1
element (smoothing)
with adjustable time constant is connected after the ramp function generator.
The ramp function generator provides the following control options via the control word
(
Z
108.1
–
):
m
Inhibit ramp generator (set output permanently to 0, ramp-down at the current limit)
m
Stop ramp generator (freeze output value)
m
Inhibit ramp generator set value (set input internally to 0, ramp-down on the ramp-down
ramp)
The following options can additionally be selected via Ramp Generator Mode
Z
110.2
–
:
m
Selection between a 16-bit parameter (
Z
110.5
–
) or a 32-bit parameter (
Z
110.4
–
) as
input value for the ramp function generator.
m
Blocking of positive or negative set values.
m
Reversal of set value sign. The internal processing sequence is inhibit before sign re-
versal.
m
Switch-off of speed set value synchronization when activating the ramp function gen-
erator.
m
Adjustment of ramp shape:
n
Trapezoidal speed profile; stepped acceleration.

There is a possibility of smoothing the speed by means of a PT
1
element.
n
S-Curve with quadratic speed profile; trapezoidal acceleration.
m
Task selection to process the set values:

The set values of the ramp function generator can either be calculated in the RT1 task
(1 ms; default) or in the fieldbus task. The setting is made by bit 16 of the
Z
110.2
–
mode.
m
Speed profile in zero-crossing at change of direction with or without rounding-off.
m
The set quick stop time
Z
110.8
–
applies to
n
change of set value from 100% to 0%
n
change of set value from actual set value at ramp function generator output
Z
110.3
–
to 0%. This causes a constant braking time from all speeds at ramp function gener-
ator output.
m
The set SS1 stop time
Z
110.21
–
applies to