Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 166)

166 Rockwell Automation Publication 750-RM002B-EN-P - September 2013
Chapter 3 Diagnostics and Protection
Input Phase Loss Detection Occasionally, three-phase power sources can fail on one phase while continuing
to deliver power between the remaining 2 phases (single-phase). Operating above
50% output under this single-phase condition can damage the drive. If such a
condition is likely, we recommend that Input Phase Loss Detection be enabled.
The drive can be programmed to turn on an alarm bit or issue a drive fault (minor
or major). The drive accomplishes this by interpreting voltage ripple on the DC
bus.
Configuring Input Phase Loss Action
P462 [InPhase LossActn]
The following bits configure Input Phase Loss action:
• “Ignore” (0) – No action is taken. This can seriously degrade the drive.
• “Alarm” (1) – Type 1 alarm indicated.
• “Flt Minor” (2) – Minor fault indicated. If running, drive continues to
run. Enable with P950 [Minor Flt Cfg]. If not enabled, acts like a major
fault.
• “FltCoastStop” (3) – Major fault indicated. Coast to Stop.
• “Flt RampStop” (4) – Major fault indicated. Ramp to Stop.
• “Flt CL Stop” (5) – Major fault indicated. Current Limit Stop.
An input phase loss is indicated in P937 [Condition Sts 1] Bit 4 “InPhaseLoss.”