Hitachi WJ200-001S Instruction Manual page 149

364
Controlled Stop Operation at Power Loss
Controlled stop operation at power loss helps avoid tripping or free-running (coasting)
of the motor when power is lost while in run mode. The inverter controls the internal
DC bus voltage while decelerating the motor, and brings the motor to a controlled stop.
Power
DC bus voltage


Under-voltage
level
Output frequency
Should power be lost while the inverter is in run mode, this function will have the
following effect:
 When the internal DC bus voltage of the inverter comes down to the set level of
B051, the inverter decreases the output frequency by the amount set in B054.
(During this interval the DC bus voltage rises due to regeneration, so does not reach
the UV level.)
 The inverter then continues deceleration according to the value set in . If the
DC bus voltage rises up to the set value of , the inverter stops deceleration to
avoid OV tripping.
 During this interval, the DC bus voltage decreases again due to lack of input power.
 When the DC bus voltage comes down to the set value of , the inverter starts
deceleration according to the set value of  again. This process will be repeated
as needed until the motor is brought to a stop.
OFF
  




