Rockwell Automation 20L, LPM20 PowerFlex 700 Active Converter Power Module - Manual (Page 32)

2-14 Start Up
PowerFlex 700L Active Converter Power Module User Manual
Publication PFLEX-UM002D-EN-P
Alone unit (DPI MASTER) and is supplying power to a common bus, extra
precaution must be taken.
Operating an Inverter with the precharge bypass open will overheat the
precharge resisters. Operating an Inverter with the Converter stopped will
draw non-sinusoidal current with peak current greater than rated and will
have significant harmonic distortion.
Control Setup The following topics discuss parameters that should be reviewed when
starting up an Active Converter.
Current Limits
Converter parameter 100 - [Active I Lmt] defines the limit on active current.
This parameter defaults to 150% of Converter rated current. Current limit
for regeneration is set in parameter 105 - [Regen I Lmt]. This defaults to
-150% of Converter rated current. When in current limit, the Converter is
unable to regulate the DC link voltage. If the drive is motoring and the
Converter is in current limit, then the DC link will drop to the peak of the
AC line. If the drive is regenerating and the Converter is in current limit, the
DC link will rise and it is up to the Inverter to limit its regenerating current
to avoid a high bus fault.
The Converter parameter 71 - [Converter Status] word bit 4 (Bus Reg Ena)
turns on when the Converter is in current limit to command the Inverter to
enable its bus voltage regulators. When the Converter is active and Bus Reg
Ena is turned off, the bus voltage regulators in the Inverter are turned off.
Line Voltage Limits
The limits on line voltage may need to be adjusted to indicate abnormal
conditions. At low line voltages, the Converter will deliver greater amps to
produce the same power. If the possible range of input voltage would result
in a condition that would exceed the rated current, then the voltage limits
must be set to guard against this condition. The low voltage and high
voltage limits have timers associated with each limit to allow brief
excursions outside of normal operating conditions. See Converter
parameters 112 -[Low Vac Lmt] through 115 - [High Vac Time].
!
ATTENTION: When operating as a Stand Alone unit (DPI
MASTER) or supplying power to a common bus, external logic
must be used to make sure the precharge bypass contactor is
closed and the Converter is running before running an Inverter.
Likewise, all Inverters must stop if the precharge opens or the
Converter stops.