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Rockwell Automation Publication 22C-UM001J-EN-E - January 2017
Chapter 1
Installation/Wiring
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 conduit box 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 an external filter with any drive rating, 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.
