External Signal For Dc Injection Braking - Hitachi L300P Series Instruction Manual

4–16
Using Intelligent Input Terminals
External Signal
for DC Injection
Braking
When the terminal [DB] is turned ON, the
DC braking [DB] feature is enabled. Set the
following parameters when the external DC
braking terminal is to be used:
• A053 – DC braking delay time setting.
The range 0.0 to 5.0 seconds.
• A054 – 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] Run or [RV]
Run terminal is ON. When the [DB]
terminal turns ON, DC braking is
applied. When the [DB] terminal turns
OFF again, the inverter output ramps to
the previous frequency.
2. Scenario 2 – The Run command is
applied from the operator keypad. When
the [DB] terminal turns ON, DC braking
is applied. When the [DB] terminal
turns OFF again, the inverter output
remains OFF.
3. Scenario 3 – The Run command is
applied from the operator keypad. When
the [DB] terminal turns ON, DC braking
is applied after the delay time set by
A053 expires. The motor is in a free-
running (coasting) condition during this
delay time. When the [DB] terminal
turns OFF again, the inverter output
remains OFF.
Opt.
Symbol Function Name
Code
07 DB External Signal for
DC Injection
Braking
C001, C002, C003, C004,
Valid for
C005
inputs:
A053, A054
Required
settings:
Notes:
• Do not use the [DB] input continuously or for
a long time when the DC braking force
setting A054 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 perfor-
mance. Use a mechanical brake for holding a
stop position.
Scenario 1
[FW, RV]
[DB]
Output
frequency
Scenario 2
Run command
from operator)
[DB]
Output
frequency
Scenario 3
Run command
from operator)
[DB]
Output
frequency
Input
Description
State
ON applies DC injection braking during
deceleration
OFF does not apply DC injection braking
during deceleration
Example: (Requires input configuration—
see page 3–43. Jumper position shown is
for –xFU/-xFR models; for –xFE models,
see page 4–11.)
TH FW
5
P24 PLC CM1
See I/O specs on page 4–8.
t
t
delay
A053
t
DB
4 3 2 1