Allen-Bradley PowerFlex 527, User Manual

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Rockwell Automation Publication 520-UM002B-EN-E - December 2017 19
Installation/Wiring Chapter 1
Ground Fault Monitoring
If a system ground fault monitor (RCD) is to be used, only Type B (adjustable)
devices should be used to avoid nuisance tripping.
Safety Ground - (PE)
This is the safety ground for the drive that is required by code. One of these
points must be connected to adjacent building steel (girder, joist), a floor ground
rod or bus bar. Grounding points must comply with national and local industrial
safety regulations and/or electrical codes.
Motor Ground
The motor ground must be connected to one of the ground terminals on the
drive.
Shield Termination - SHLD
Either of the safety ground terminals located on the power terminal block
provides a grounding point for the motor cable shield. The
motor cable shield
connected to one of these terminals (drive end) should also be connected to the
motor frame (motor end). Use a shield terminating or EMI clamp to connect the
shield to the safety ground terminal. The earthing plate or conduit box option
may be used with a cable clamp for a grounding point for the cable shield.
When shielded cable is used for control and signal wiring , the shield should be
grounded at the source end only, not at the drive end.
RFI Filter Grounding
Using a drive with filter may result in relatively high ground leakage currents.
Therefore, the
filter must only be used in installations with grounded AC
supply systems and be permanently installed and solidly grounded (bonded)
to the building power distribution ground. Ensure that the incoming supply
neutral is solidly connected (bonded) to the same building power distribution
ground. Grounding must not rely on flexible cables and should not include any
form of plug or socket that would permit inadvertent disconnection. Some local
codes may require redundant ground connections. The integrity of all
connections should be periodically checked.