B2: Dc Injection Braking - YASKAWA U1000 Series Technical Manual

5.2 b: Application
 b2: DC Injection Braking
b2 parameters determine operation of the DC injection braking and Zero speed control features.
b2-01: DC Injection Braking Start Frequency

b2 parameters determine operation of the DC Injection Braking and Zero Speed Control features.
No.
b2-01
The function triggered by parameter b2-01 depends on the control mode that has been selected.
OLV/PM, AOLV/PM, V/f, V/f w/PG and OLV (A1-02 = 0, 1, 2, 5, 6)
For these control modes, parameter b2-01 sets the starting frequency for DC Injection Braking at stop. Once the output
frequency falls below the setting of b2-01, DC Injection Braking is enabled for the time set in parameter b2-04.
Figure 5.16
Note: If b2-01 is set to a smaller value than parameter E1-09 (minimum output frequency), then DC Injection Braking will begin as
soon as the frequency falls to the value set to E1-09.
CLV and CLV/PM (A1-02 = 3, 7)
For these control modes, parameter b2-01 sets the starting frequency for Zero Speed Control (not position lock) at stop.
Once the output frequency falls below the setting of b2-01, Zero Speed Control is enabled for the time set in parameter
b2-04.
Figure 5.17
Note: If b2-01 is set to lower than the minimum output frequency (E1-09), then Zero Speed Control begins at the frequency set to
E1-09.
b2-02: DC Injection Braking Current

Sets the DC Injection Braking current as a percentage of the drive rated current. If set larger than 50%, the carrier
frequency is automatically reduced to 4 kHz.
No.
b2-02
The level of DC Injection Braking current affects the strength of the magnetic field attempting to lock the motor shaft.
Increasing the current level will increase the amount of heat generated by the motor windings. This parameter should
only be increased to the level necessary to hold the motor shaft.
b2-03: DC Injection Braking Time at Start

Sets the time of DC Injection Braking (Zero Speed Control when in CLV and CLV/PM) at start. Used to stop a coasting
motor before restarting it or to apply braking torque at start. Disabled when set to 0.00 s.
No.
b2-03
Note: Before starting an uncontrolled rotating motor (e.g., a fan motor driven by windmill effect), DC Injection or Speed Search should
be used to either stop the motor or detect its speed before starting it. Otherwise motor stalling and other faults can occur.
154
Name
DC Injection Braking Start Frequency
common_
E1-09 Min. Output
TMonly Frequency
b2-01 DC Injection
Braking Start Frequency
Output
frequency
Figure 5.16 DC Injection Braking at Stop for V/f, V/f w/PG and OLV
common_
E1-09 Min. Output
TMonly
Frequency
b2-01 DC Injection
Braking Start Frequency
Output
frequency
Figure 5.17 Zero Speed Control at Stop in CLV and CLV/PM
Name
DC Injection Braking Current
Name
DC Injection Braking Time at Start
Setting Range
0.0 to 10.0 Hz
DC Injection
Braking
Time
b2-04
Zero Speed
Control
b2-04
Setting Range
Setting Range
0.00 to 10.00 s
YASKAWA ELECTRIC SIEP C710636 03A YASKAWA U1000 Technical Manual
Default
Determined by A1-02
Time
Default
0 to 100%
Default
0.00 s
50%