General grounding requirements – Rockwell Automation 23P PowerFlex Digital DC Drive User Manual
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Rockwell Automation Publication 20P-UM001K-EN-P - July 2014
Chapter 1
Installation and Wiring
General Grounding
Requirements
The drive Safety Ground (PE) must be connected to system ground.
Ground
impedance must conform to the requirements of national and local industrial
safety regulations and electrical codes. Periodically check the integrity of all
ground connections.
For installations within a cabinet, use a safety ground point or ground bus bar
connected directly to building steel. Ground all circuits, including the AC input
ground conductor, independently and directly to this point/bar.
For installations in distribution systems that have ungrounded or high
impedance, neutral connections or systems, see Grounding for Installations in an
Ungrounded or High-Impedance, Neutral Ground, or System on page
Figure 9 - Typical Grounding
ATTENTION: To comply with the essential requirements of the CE Low Voltage
Directive 2006/95/EC, PowerFlex DC drives cannot be powered from a corner-
earthed (TN with one phase earthed) supply system. When operating PowerFlex
DC drives from an IT or impedance-earthed supply system, only temporary
operation is permitted after an earth fault is detected in the power system.
L1
L2
L3
U
V
W
C
D
PE1/
STS
PORT
MOD
NET A
NET B
Earth
All wires (including motor
ground) must be connected
inside the motor terminal box.
Transformer
Safety
Ground
AC
M
ai
ns
S
up
pl
y
AC Line Reactor