Hitachi WJ Series User Manual page 220

Chapter 9
DC braking force and carrier frequency
!
 If "Carrier Frequency [b083]" is greater than 2 kHz, the DC braking force is limited as shown in
the figure below.
DC braking using the "External DC braking [DB]" terminal
A
 When applying DC braking using input signals from the control terminal, assign "External DC
braking [DB] (07)" to the input terminal.
 DC braking using the [DB] terminal is only available when the "DC braking selection [A051]" =
00, 01. DC braking is activated when the [DB] terminal is turned on, regardless of the RUN
command.
 DC braking operation varies depending on the edge operation/level operation settings in the
"DC braking operation method selection [A056]". Configure edge operation or level operation
settings to match the system in use, referring to the operation examples provided in the figure
below. When edge operation is selected, set the "DC braking active time at stop [A055]".
◼ (Example 1) Turning the [DB] terminal ON/OFF during operation.
(Example 1-a) [A056] = "Edge operation (00)"
RUN
command
[DB] terminal
Output
frequency
DC braking
* In the case of edge operation, DC braking is applied for the duration of the [A055] setting from the ON edge input on the [DB] terminal.
In the case of level operation, DC braking is applied while the [DB] terminal is on.
◼ (Example 2) When turning [DB] terminal on/off during inverter deceleration when the RUN command is off.
The [A053] setting is 0.0 (s).
(Example 2-a) [A056] = "Edge operation (00)"
RUN
command
[DB] terminal
Output
frequency
DC braking
* When the "DC braking delay time [A053]" is 0.0 (s), DC braking is immediately applied when the [DB] terminal is turned on.
◼ (Example 3) When the "DC braking delay time [A053]" is set to a value other than 0.0 (s), and the same operation
as that described in (Example 2) above is performed.
(Example 3-a) [A056] = "Edge operation (00)"
RUN
command
[DB] terminal
Output
frequency
DC braking
* If a value other than 0.0 (s) is set as the "DC braking delay time [A053]", DC braking is applied after free run (output shutdown) for the
allotted time. However, DC braking is immediately applied if the [DB] terminal is turned on when the inverter is stopped.
100
Maximum
50
braking force (%)
10
0
Carrier frequency [b083] (kHz)
ON
ON
[A055]
ON
ON
[A055]
ON
ON
Free running
[A055]
[A053]
(100)
(50)
(10)
2 3 5 9 11 13 15
7
(Example 1-b) [A056] = "Level operation (01)"
RUN
command
[DB] terminal
Output
frequency
DC braking
(Example 2-b) [A056] = "Level operation (01)"
RUN
command
[DB] terminal
Output
frequency
DC braking
(Example 3-b) [A056] = "Level operation (00)"
RUN
command
[DB] terminal
Output
frequency
DC braking
9-7-12
Inverter Functions
ON
ON
ON
ON
ON
ON
Free running
[A053]