Rockwell Automation 20D PowerFlex 700S with Phase I Control Reference Manual - Manual (Page 98)

98 Rockwell Automation Publication PFLEX-RM002D-EN-E - August 2013
Chapter 1 Detail Drive Configuration and Operation
Flux Only: The drive's torque is set to zero when a power disturbance is detected.
The motor flux is continued until the disturbance goes away or until a power
down occurs (extended power loss). If the power loss is of a very short duration or
there is sufficient input impedance to limit the inrush current when power
returns, the drive will continue normal operation after the disturbance passes.
However, if the power returns causing a large inrush current (precharge device is
still bypassed) drive damage is likely.
Ride Through Timeout Fault
Parameter 407 [Power Loss Time] sets the duration or time delay allowed for the
incoming power to return before a ride through fault occurs. This limits the time
where an auto-start for the drive could occur. The default value for this time is 2
seconds with a minimum value of 0 seconds and a maximum value of 60 seconds.
The ride through timeout fault is shown in Parameter 321 [Exception Event2]
bit 8 “RidethruTime.” The ride through timeout fault will inhibit the drive auto
start function requiring a fault clear and commanded start to run the drive again.
Precharge Operation
The drive will not run until the controller's precharge function has completed.
Also, the precharge function in the drive runs independent of drive precharge
hardware (for the most part) and the hardware control. The drive will not restart
precharge any time that the drive is running (see ride through above). The drive
control is in precharge (or bus capacitor charging mode) any time that the
precharge is not “done” (see parameter 555 [MC Status] bit 11 “PreChrg Done”).
This is independent of whether or not the drive control actually controls the
precharge hardware.
IMPORTANT The user must determine the safe time that will be allowed for the drive to
auto-start.