Mike Dolt Enterprises
Mike Dolt Enterprises
User: utilguy, Location: southeastern georgia
Asked on: Thursday, April 14, 2011 at 8:48 am EDT
Answered on: Tuesday, May 14, 2024 at 4:11 am EDT
Question: We're installing an auto transfer switch ahead of an existing main service panel. The 2 feeds will be from separate padmounted transformers on different distribution systems. The neutral conductors would normally be grounded in the transformers. The plan is to install service entrance disconnects between each transformer and the ATS. It seems the neutrals should be grounded and bonded in each new service disconnect (correct?) but would there need to be changes made in the existing service panel too?thanks
Neutral Grounding and Bonding
Yes, the neutral conductors should be grounded and bonded in each new service disconnect as follows: Equipment Grounding Conductor (EGC)
Connect the neutral conductor to the EGC bus bar in the service disconnect.
Neutral Bonding Jumper
Install a bonding jumper between the EGC bus bar and the enclosure of the service disconnect.
Existing Service Panel
No changes are typically required in the existing service panel, as long as the following conditions are met: The existing service panel is grounded and bonded in accordance with the National Electrical Code (NEC). The new service entrances and ATS are installed in compliance with the NEC. The grounding electrode system is adequate for both the existing service and the new service entrances.
Additional Considerations Ensure that the clearances and working space requirements of the NEC are met for both the new service disconnects and the existing service panel. Consult with a qualified electrician to verify the specific requirements and ensure proper installation. Notify the utility company of the changes to the electrical system, as they may need to inspect the installation and update their records. Flag for review