Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 75)

Rockwell Automation Publication 750-RM002B-EN-P - September 2013 75
Drive Configuration Chapter 1
The inverter output is disabled and the motor coasts if the output frequency
drops to zero or if the bus voltage drops below Vopen or if any of the Run Permit
inputs are de-energized.
If the drive is still in inertia ride through operation when power returns, the drive
immediately accelerates at the programmed rate to the set speed. If the drive is
coasting and it is in a Run Permit state, the reconnect algorithm is run to match
the speed of the motor. The drive then accelerates at the programmed rate to the
set speed.
Continue
This mode provides the maximum power ride through. The input voltage can
drop to 50% and the drive is still able to supply drive rated current (not drive
rated power) to the motor.
ATTENTION: To guard against drive damage, a minimum line impedance must
be provided to limit inrush current when the power line recovers. Provide an
input impedance that is equal to or greater than the equivalent of a 5%
transformer with a VA rating 6 times the drive’s input VA rating.
Drive damage can occur if proper input impedance is not provided as explained
below. If the value for [Power Loss Level] is greater than 18% of [DC Bus Memory],
you must provide a minimum line impedance to limit inrush current when the
power line recovers. Provide input impedance that is equal to or greater than the
equivalent of a 5% transformer with a VA rating 5 times the drives input VA rating.
Bus Voltage
Motor Speed
Power Loss
Output Enable
Pre-Charge
Drive Fault
680V
620V
560V
500V
407V
305V
Bus Voltage
Motor Speed
Power Loss
Output Enable
Pre-Charge
Drive Fault
680V
620V
560V
365V
305V