Approved2018
New member
- Location
- Atlanta, GA, USA
Working on a project where the utility company transformer (4,160V secondary) has a 400 Amp at 10 sec neutral grounding resistor.
The utility company transformer is around 500 ft from the Service Entrance rated (SER) switchgear.
We specified 3/C plus ground from the transformer to our SER switchgear.
However, the utility company doesn't allow us to connect the service feeder ground cable to their system.
Is that OK not to have the substation ground grid and the Facility ground grid connected?
As I understand, the ground cable between SER switchgear ground bus and the NGR ground side would provide a more effective ground path for protection relays to faster react to a ground fault.
Or is it OK by NEC not to have this ground connection?
The utility company transformer is around 500 ft from the Service Entrance rated (SER) switchgear.
We specified 3/C plus ground from the transformer to our SER switchgear.
However, the utility company doesn't allow us to connect the service feeder ground cable to their system.
Is that OK not to have the substation ground grid and the Facility ground grid connected?
As I understand, the ground cable between SER switchgear ground bus and the NGR ground side would provide a more effective ground path for protection relays to faster react to a ground fault.
Or is it OK by NEC not to have this ground connection?