The system has a ground bus bar inside or outside located at an appropriate place to which all internal grounding connections are returned. Once the final ground bus bar is connected to an actual earth pit or earth grid that the system gets finally earthed. The National Electrical Code (NEC), section 430-L, defines the motor grounding conditions. See the pictures for different alternatives. Design the cabinet so that the control. Improper grounding or earthing of “Distributed Control Systems (DCS)” or “Power Electronic Systems (PES)” can result in either mal-operation of the system / controller or failure of electronic control cards or sometimes even the embedded control software getting erased. This is known as the "PEN split point / point".
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