Rockwell Automation 20Y PowerFlex Active Front End - Manual (Page 28)

28 Rockwell Automation Publication 20Y-UM001E-EN-P - July 2014
Chapter 1 AFE in IP20 2500 MCC Style Enclosure—Installation/Wiring
AC Supply Source
Considerations The AFE Frame 10 or Frame 13 in a IP20 2500 MCC Style enclosure is suitable
for use on a circuit capable of delivering 100,000 rms symmetrical amperes at
400/480V and 65,000 rms symmetrical amperes at 600/690V.
The AFE must not be used on undersized or high-impedance supply systems.
The supply system kVA must be equal to or greater than the drive-related kW, and
the system impedance must be less than 10%. Operation outside these limits can
cause instability resulting in AFE shutdown.
System Impedance = (PowerFlex 700AFE kVA ÷ Transformer kVA) x Transformer % Impedance
You must take into account the kVA of all PowerFlex AFEs on the distribution
system and the system impedance of upstream transformers.
If a Residual Current Detector (RCD) is used as a system ground fault monitor,
use only Type B (adjustable) devices to avoid nuisance tripping.
Unbalanced, Ungrounded, or Resistive Grounded Distribution
Systems
If phase-to-ground voltage will exceed 125% of normal or the supply system is
ungrounded, see Wiring and Grounding Guidelines for Pulse Width Modulated
(PWM) AC Drives, publication DRIVES-IN001, for more information.
Input Power Conditioning
Certain events on the power system supplying an AFE can cause component
damage or shortened product life. This includes the following events:
• The power system has power factor correction capacitors switched in and
out of the system, either by the user or by the power company.
ATTENTION: To guard against personal injury and/or equipment damage caused
by improper fusing or circuit breaker selection, use only the recommended line
fuses or circuit breakers specified in
Appendix A .
ATTENTION: The PowerFlex Active Front End has not been designed to be used
on IT (insulated tera) or corner-grounded power networks above 600V (phase-to-
phase voltage). Operation on such a network can cause a hazardous failure of the
insulation system of the AFE.
ATTENTION: The LCL Filter of the PowerFlex Active Front End contains common
mode capacitors that are referenced to ground. These devices must be
disconnected if the AFE is installed on a resistive grounded distribution system or
an ungrounded distribution system. See
Figure 18 on page 39 or Figure 19 on
page 40 for jumper locations.