32 Operation and settings
4.3.5 The menu "ACCELERATING"
Contents: In menu "Accelerate", the acceleration ramp is defined. In addition, it is possible to optimize
the start-up reaction.
Figure 4.11 Effect of the parameters
Description of the parameters:
A_POS
Presetting of the positive
acceleration.
R_POS1
Canging the upper or lower
R_POS2
rounding, if necessary. A greater
value causes a smoother rounding.
T_VB
Pre-braking period: Maximum time
from switching the contact "MB -
mechanical brake" until the speed
regulation starts.
M_VB
Pre-braking torque:
Size of the d.c.-"brake"-part during
the time T_VB.
M_0
Starting torque:
Size of the a.c.-"drive"-part after the
time T_VB.
An optimum start-up reaction requires that the
main contactor is switched on with the exit "RB".
This is the only guarantee that the main
contactor is switched in the currentless state.
The control device opens the mechanical brake
via the relay output "MB".
In order to avoid that the motor works against
the brake that opens, the start-up process is
decelerated by means of the pre-braking period
T_VB
.
In this period of time, the d.c. winding of the
motor is impinged with a direct voltage, the pre-
braking torque
M_VB.
In order to avoid that the motor turns back too
heavily or to overcome an initial breakaway
torque, it is possible to connect the starting
torque
M_0
at the beginning of the run.
-> The optimization of the start-up reaction is
described in detail in chapter 5
Commissioning.
V_3
t
RF
V1
V3
RV1
MB
inputs
outputs
RV2
0
RB
Accelerating
T_VB
"drive"
"brake"
A_POS
R_POS2
R_POS1
M0
M_VB
DC-motor-winding
AC-motor-winding
motor
.
>Acceleration
R_POS1
ACCELERATING
**************************
A_POS
R_POS2
T_VB
M_VB
25 %
0.70 m/s2
40 %
50 %
100 ms
M_0
5 %
>Pre. braking torque
>Prelimary braking time
>Starting torque
>Rounding1
>Rounding 2
.
