Rockwell Automation 1336T Wiring and Grounding Guide, (PWM) AC Drives - Manual (Page 54)

54 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014
Chapter 3 Grounding
Effective Grounding Practices
This scheme replaces the conduit with shielded or armored cable that has a PVC
exterior jacket. This PVC jacket prevents accidental contact with building steel
and reduces the possibility that noise can enter the ground grid.
Optimal – Recommended Grounding Practices
The fully grounded scheme provides the best containment of common mode
noise. It uses PVC jacketed, shielded cable on both the input and the output to
the drive. This method also provides a contained noise path to the transformer to
keep the ground grid as clean as possible.
X0
R
S
T
U
V
W
PE PE
A
B
C
PE
Input Transformer AC Drive
Motor Frame
Motor
Connection to Drive Structure or
Optional Cabinet Via Grounding
Connector or Terminating Shield
at PE Terminal
Motor Frame
Ground
Connection to Ground Grid,
Girder, or Ground Rod
Connection to Cabinet Ground Bus
or Directly to Drive PE Terminal
Panel Ground Bus
Optional Enclosure
Building Ground Potential
Shielded or Armored
Cable with PVC Jacket
PVC
X0
R
S
T
U
V
W
PE PE
A
B
C
PE
Input Transformer
Shielded or
Armored Cable
with PVC Jacket
Shielded or
Armored Cable
with PVC Jacket AC Drive
Motor Frame
Motor
PVC PVC
Motor Frame
Ground
Connection to Drive Structure or
Optional Cabinet Via Grounding
Connector or Terminating Shield
at PE Terminal Panel Ground Bus
Optional Enclosure
Connection to Cabinet
Ground Bus or Directly
to Drive PE Terminal
Building Ground Potential
Connection to Drive
Structure or Optional
Cabinet Via Grounding
Connector or Terminating
Shield at PE Terminal
Connection to Ground Grid,
Girder or Ground Rod