Lenze 8400 motec Series, Software Manual, Page: 329 / 376

Firmware
≤
02.00 - DMS 2.1 EN - 03/2011
L
329
8400 motec | Software Manual
Function library
L_PCTRL_1
12.3.2 Ramp function generator
The PID output is led via a ramp function generator with linear characteristic. This serves
to transfer setpoint step-changes at the PID output into a ramp which should be as steep
as possible.
[12-5] 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.
–
C00227 : Acceleration time T
ir
– C00228 : Deceleration time T
if

The t
ir
/t
if
values are converted into the required Ti times according to the following
formula:

The ramp function generator is immediately set to "0" by setting bInAct to TRUE.
12.3.3 Operating range of the PID process controller
The value range of the input signal nSet_a and thus the operating range of the PID process
controller can be limited with the following parameters:

C00231/1 : Pos. maximum (default setting: 199.9 %)

C00231/2 : Pos. minimum (default setting: 0.0 %)

C00231/3 : Neg. minimum (default setting: 0.0 %)

C00231/4 : Neg. maximum (default setting: 199.9 %)
12.3.4 Evaluation of the output signal
After the limitation, the output signal is evaluated with the influencing factor nInflu_a .
The evaluation is activated/suppressed along a ramp when the input
bEnableInfluenceRamp is set to TRUE. The ramp times are set with the parameters
"Acceleration time influence" ( C00243 ) and "Deceleration time influence" ( C00244 ).
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
–
---------------------- ⋅
=