Application Constants: B; Dc Injection Braking: B2-01 To B2-04; Dc Injection Braking Timing Chart - YASKAWA VARISPEED-616G5 Instruction Manual

7.5.1 Application Constants: b

DC Injection Braking: b2-01 to b2-04

J
The DC injection braking function decelerates by applying a DC current to the motor. This happens
D
in the following two cases
DC Injection Braking Time at Start:
•
Effective for temporarily stopping and then restarting, without regenerative processing, a motor
coasting by inertia.
DC Injection Braking Time at Stop:
•
Used to prevent coasting by inertia when the motor is not completely stopped by normal decelera-
tion when there is a large load. The stopping time can be shortened by lengthening the DC injection
braking time or increasing the DC injection braking current.
User User
Constant
Number
Zero speed level
(DC injection brak-
b2-01
ing starting frequen-
cy)
DC injection braking
b2-02
current
DC injection braking
b2-03
time at start
DC injection braking
b2-04
time at stop
For the zero speed level (b2-01), set the frequency for beginning DC injection braking for deceleration.
D
If the excitation level is lower than the minimum output frequency (E1-09), the DC injection braking
will begin from the minimum output frequency.
In flux vector control mode, DC injection braking becomes the initial excitation starting frequency at
D
the time of deceleration. In that case, braking starts from the excitation level regardless of the minimum
output frequency setting.
The excitation level is also used as the operating frequency for the zero servo function (for flux vector
D
control only).
For the DC injection braking current (b2-02), set the value for the current that is output at the time of
D
DC injection braking. DC injection braking current is set as a percentage of Inverter rated output cur-
rent, with the Inverter rated output current taken as 100%.
For the DC injection braking time at start (b2-03), set the DC injection braking operating time for when
D
the motor is started.
For the DC injection braking time at stop (b2-04), set the DC injection braking operating time for when
D
the motor is stopped.
When the DC injection command (initial excitation command) for multi-function input terminals is
D
used at the same time, open the terminal input, and perform DC injection braking only for the period
of time set under b2-03.
Figure 7.19 provides a timing chart of DC injection braking (initial excitation).
D
Output frequency
Fig 7.19
Change g
during during Setting Setting
Name
Opera- Range
tion
0.0 to 10.0
×
0 to 100
×
0.00 to
×
10.00
0.00 to
×
10.00
E1-09
(Min. output frequency)
b2-03
(DC injection braking time at start)

DC Injection Braking Timing Chart

7 - 43
7.5 Common Functions
Valid Access Levels
Unit Factory Factory
V/f V/f with
Setting
Control PG
B B
Hz 0.5
% 50 B B
s 0.00 B B
B B
s 0.50
(DC injection braking
time at stop)
Open
Flux
Loop
Vector
Vector
B B
B
×
B B
B B
7
The larger of
b2-01 or
E1-09
Time
b2-04