Vacon CX, Руководство пользователя

Страница: 37 / 52

Vacon Plc
Phone: +358-(0)201 2121 Fax: +358-(0)201 212 205
Service: +358-40-8371 150 E-mail: vacon@vacon.com
Page 36 V V V V Vacon acon acon acon acon Multi-purpose Control Application II Multi-purpose Control Application II
Multi-purpose Control Application II Multi-purpose Control Application II
Multi-purpose Control Application II
4. 9 4. 9 4. 9 4. 9 4. 9 DC braking time at stop DC braking time at stop DC braking time at stop DC braking time at stop DC braking time at stop
Defines if braking is ON or OFF and the braking time of the DC-brake when the motor
is stopping. The function of the DC-brake depends on the stop function, parameter
4
. .
. .
. 7. See figure 6-21.
0 0
0 0 0 DC-brake is not used
>0 >0 >0 >0 >0 DC-brake is in use and its function depends on the Stop function,
(param. 4
..... 7), and the time depends on the value of parameter 4 ..... 9:
Stop-function = 0 (coasting):
After the stop command, the motor coast to a stop without any control from
the frequency converter.
With DC-injection, the motor can be electrically stopped in the shortest possible
time, without using an optional external braking resistor.
The braking time is scaled according to the frequency when the DC-
braking starts. If the frequency is >nominal frequency of the motor (par. 1.11),
setting value of parameter 4.9 determines the braking time. When the frequency
is <10% of the nominal, the braking time is 10% of the set value of parameter
4.9.
t = param. 4. 9
t
Param. 4. 10
fout
UD009K23
Motor speed
Output frequency
DC-braking
RUN
STOP
After the Stop command, the speed of the motor is reduced according to
the set deceleration parameters, as fast as possible, to a speed defined with
the parameter 4
..... 10, where the DC-braking starts.
Figure 6-21 DC-braking time when stop = coasting.
Stop-function = 1 (ramp):
0,1x f
n
with parameter 4 ..... 9.
If high inertia exists, it is
recommended to use an
external braking resistor for
faster deceleration. See
figure 6-22.
Figure 6-22 DC-braking
time when stop function =
ramp.
fout
fout
fn
fn
t t
t = 1 x par. 4. 9
t = 0.1 x par. 4. 9
UD009K21
RUN
STOP
RUN
STOP
Output frequency
Motor speed
Output frequency
Motor speed
DC-braking ON
DC-braking ON
The braking time is defined