Hitachi WJ200-001L, Инструкция по эксплуатации, Страница: 227 / 680

4

20
External Signal for DC Braking
When the terminal [DB] is turned ON, the
DC braking feature is enabled. Set the
following parameters when the external DC
braking terminal [DB] is to be used:


– DC braking delay time setting.
The range is 0.1 to 5.0 seconds.


– DC braking force setting. The
range is 0 to 100%.
The scenarios to the right help show how DC
braking works in various situations.
1. Scenario 1 – The [FW] or [RV] terminal is
ON. When [DB] is ON, DC braking is
applied. When [DB] is OFF again, the
output frequency ramps to the prior level.
2. Scenario 2 – The Run command is applied
from the operator keypad. When the [DB]
terminal is ON, DC braking is applied.
When the [DB] terminal is OFF again, the
inverter output remains OFF.
3. Scenario 3 – The Run command is applied
from the operator keypad. When the [DB]
terminal is ON, DC braking is applied
after the delay time set by

expires.
The motor is in a free-running (coasting)
condition. When the [DB] terminal is OFF
again, the inverter output remains OFF.
Option
Code
Terminal
Symbol
Function Name State Description

DB External DC
Braking ON Applies DC injection braking during deceleration
OFF Does not apply DC injection braking during
deceleration
Valid for inputs:

~

Example (requires input configuration
—see
page 3-85 ):
See I/O specs on
page 4
–6.
Required settings

,

Notes:

Do not use the [DB] input continuously or for a
long time when the DC braking force setting

is high (depends on the motor application).

Do not use the [DB] feature for continuous or high
duty cycle as a holding brake. The [DB] input is
designed to improve stopping performance. Use a
mechanical brake for holding a stop position.
[FW,RV]
1
0
[DB]
1
0
Output
frequency
Scenario 1
t
Run command
from operator
1
0
[DB]
1
0
Output
frequency
Scenario 2
t
Run command
from operator
1
0
[DB]
1
0
Output
frequency
Scenario 3
t
delay

DB
7 6 5 4 3 2 1 L P24 PLC