5 ramp function generator for the main setpoint, 6 s-shaped ramp, 12 function library – Lenze 8400 motec User Manual
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Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05
449
12
Function library
12.2
L_NSet_1
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12.2.5
Ramp function generator for the main setpoint
The setpoint is now led via a ramp function generator with linear characteristic. The ramp function
generator converts setpoint step-changes at the input into a ramp.
[12-4] Acceleration and deceleration times
• t
ir
and t
if
are the desired times for changing between w1 and w2.
• The ramps for acceleration and deceleration can be set individually.
•
: Acceleration time t
ir
•
: Deceleration time t
if
• The t
ir
/t
if
values are converted into the required Ti times according to the following formula:
• When the bRfg0 output is set to TRUE, the ramp function generator brakes to 0 along its
deceleration ramp.
12.2.6
S-shaped ramp
A PT1 element is connected downstream of the linear ramp function generator. This arrangement
implements an S-shaped ramp for a nearly jerk-free acceleration and deceleration.
• The PT1 element can be switched on/off via
.
• The corresponding S-ramp time can be set under
w1, w2 = change of the main setpoint as a function of t
ir
and t
if
RFG-OUT = output of the ramp function generator
RFG-OUT
100 %
w2
w1
t
0 %
t
ir
t
ir
T
ir
T
ir
T
ir
t
ir
100 %
w2 w1
–
-----------------------
⋅
=
T
if
t
if
100 %
w2 w1
–
-----------------------
⋅
=