Hitachi SJ2002 Series Instruction Manual page 123

The graph below shows an inverter output profile that starts decelerating to a stop. At
two different points during the deceleration, regenerative voltage elevates the DC bus
level, exceeding the LADSTOP threshold set by B131. When the Over-voltage
LADSTOP feature is enabled by B130 = 01, the inverter stops the deceleration ramp in
each case until the DC bus level is again less than the threshold value.
B130 = 01 OVLADSTOP = enable
Over-voltage protection
trip threshold
Over-voltage
LADSTOP threshold
DC bus level
frequency
When using the Over-voltage LADSTOP feature, please note the following:
• When the over-voltage LADSTOP feature is enabled (B130 = 01), the actual
deceleration is sometimes longer than the value set by parameters F003/F203.
• The over-voltage LADSTOP feature does not operate by maintaining a constant
DC bus voltage. So, it is still possible to have an over-voltage trip event during
extreme deceleration.
• If B131 is set lower than the normal DC bus voltage (when not in decel) by mistake, or
if the inverter's input voltage increases enough, then the inverter will apply LADSTOP
(if enabled) all the time. In this case, the inverter can accelerate and run the motor, but
it cannot decelerate. If you are not sure that B131 > DC bus voltage, measure the DC
bus voltage in your installation and verify that the B131 value is higher.
"B" Function
Func. Name /
Code SRW Display
B130 Over-voltage
LADSTOP enable
OVLADSTOP
V
B131
Output
Start
deceleration
Description
Pauses deceleration ramp when
DC bus voltage rises above
threshold level, in order to
OFF
avoid over-voltage trip.
Two option codes:
00 .. Disable
01 .. Enable
SJ200
Inverter stops
deceleration
Deceleration
resumed
Run
Mode
–FE(F)
Edit
(EU)
Lo Hi
✘ ✔
00
3–43
Inverter
2
t
t
Defaults
–FU
Units
(USA)
00 —