Fuji Electric FRENIC-Ace series, User Manual

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5.3 Description of Function Codes
5-72
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Restart mode after momentary power failure (Continuous running level) (H15)
Continued operation at the momentary power failure (P, I) (H92, H93)
• Trip after momentary deceleration is stopped
When trip after deceleration stopped is selected (F14 = 2), at momentary power failure restart operation (Mode
selection), momentary power failure occurs while operating the inverter, and deceleration stop control starts when
DC link bus voltage of the inverter becomes at or drops below the continuous running level.
Adjust voltage level of DC link bus to start deceleration stop control by H15.
Under decelerate-to-stop control, the inverter decelerates its output frequency keeping the DC link bus voltage
constant using a PI regulator.
P (proportional) and I (integral) components of the PI regulator are specified by H92 and H93, respectively.
For normal inverter operation, it is not necessary to modify data of H15, H92 or H93.
• Continue to run
When momentary power failure restart operation (Continue to run) is selected (F14 = 3) at momentary power
failure restart (operation selection), momentary power failure occurs while operating the inverter and continue to
run control starts when DC link bus voltage of the inverter becomes at or drops below the continue to run level.
Adjust continue to run level to start continue to run control by H15.
Under the continue to run control, the inverter continues to run keeping the DC link bus voltage constant using the
PI regulator.
P (proportional) and I (integral) components of the PI regulator are specified by H92 and H93, respectively.
For normal inverter operation, it is not necessary to modify data of H15, H92 or H93.
Power supply group
Alpha ( α )
22 kW or below 30 kW or above
200 V 5 V 10 V
400 V 10 V 20 V
Even if “Deceleration stop control” or “Continue to run”, is selected, the inverter may not be able to
perform the function when the inertia of the load is small or the load is heavy, due to undervoltage
caused by the control delay. In such a case, when “Deceleration stop control” is selected, the inverter
allows the motor to coast to a stop; when “Continue to run” is selected, the inverter saves the output
frequency being applied when the undervoltage alarm occurs and perform momentary power failure
restart operation.
When the input power voltage for the inverter is high, setting the continue to run level high makes the
control more stable even if the inertia of the load is relatively small. Raising the continuous running level
too high, however, might cause the continue to run control activated even during normal operation.
When the input power voltage for the inverter is extremely low, continue to run control might be activated
even during normal operation, at the beginning of acceleration or at an abrupt change in load. To avoid
this, lower the continuous running level. Lowering it too low, however, might cause undervoltage that
results from voltage drop due to the control delay.
Before you change the continuous running level, make sure that the continuous running control will be
performed properly, by considering the fluctuations of the load and the input voltage.
Power failure
Power restoration
DC link bus
voltage
Undervoltage level
Continuous running reset level (H15 + α)
Continuous running level (H15)
Inverter output
frequency