Hitachi SJ Series User Manual page 329

Chapter 12
12.14.2 Starting with DC braking
Q
• How to start after having rotation fan stopped
• How to start operation after having rotating motor
stopped
A
• Before outputting the frequency to the motor, apply
DC braking to stop the motor rotating. And then,
start operation.
• To use DC braking for starting, the following
settings are required:
- Set [AF101] DC braking selection to 01
- Set [AF102] Braking mode selection to 00
- Set [AF109] DC braking time for starting to
other than 0.0
• In DC braking for starting, DC braking is performed,
after the operation command is given, for the
period of time set for the DC braking time for
starting [AF109].
Parameter
Item
DC braking selection
Braking mode selection
DC braking force for
starting
DC braking time for
starting
!
• If [AF101] DC braking selection is set to 02, DC
braking will be started when both the frequency
command and the output frequency become equal
to or lower than [AF103]
regardless of whether the motor is running or
stopped. See "12.15.2 Stopping with DC braking"
for details.
Parameter Data
00
01
[AF101]
02
[AF102] 00
[AF108] 0~100(%)
[AF109] 0.0~60.0(s)
DC braking frequency setting
12-14-2
!
• Depending on the set braking force, the carrier
frequency may automatically go down to protect
the inverter.
• When setting or operating [AF108] DC braking
force for starting and [AF109] DC braking time for
starting, pay attention to heat generation on the
motor.
Example of a case where the DC braking function
for starting is applied
FW
Output
frequency
Internal DC braking: Disabled
Internal DC braking: Enabled
Internal DC braking: Enabled (operable only at the
set frequency)
Enables the DC braking.
Adjusts the DC braking force. The maximum braking
force is achieved when set to 100%.
Valid when the internal DC braking is enabled.
Starts the DC braking when the operation command
is turned on.
• If [AF102] Braking mode selection is set to other
than 00, see "12.14.9 Starting after applying
servo-lock".
,
Inverter Function
ON
DC braking
[AF109]
Description