Hitachi SJ2002 Series Instruction Manual page 159

External Signal for DC Braking
When the terminal [DB] is turned ON, the
DC braking feature is enabled. Set the follow-
ing parameters when the external DC braking
terminal [DB] is to be used:
• A053 – DC braking delay time setting. The
range is 0.1 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] 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 A053 expires.
The motor is in a free-running (coasting)
condition. When the [DB] terminal is OFF
again, the inverter output remains OFF.
Option Terminal
Code Symbol
07 DB External DC Braking
C001, C002, C003, C004,
Valid for inputs:
C005, C006
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 performance. Use a
mechanical brake for holding a stop position.
Input
Function Name
State
ON
OFF
SJ200
1
[FW, RV]
0
1
[DB]
0
Output
frequency
1
Run command
0
from operator
1
[DB]
0
Output
frequency
1
Run command
0
(from operator)
1
[DB]
0
Output
frequency
Description
applies DC injection braking during deceleration
does not apply DC injection braking during
deceleration
Example (requires input configuration—see
page 3–45):
L 6 5 4
See I/O specs on page 4–6.
4–17
Inverter
2
Scenario 1
t
Scenario 2
t
Scenario 3
delay
A053
t
DB
3 2 1 PCS