phil_edwards123
Member
- Location
- vancouver, BC, canada
According to NEC, each separately derived system must be system bonded and also grounded (earthed) to a suitable grounding electrode (such as water pipe or structural beam, etc).
In the example below in which the Delta-Wye transformer is installed in a tenant space. There is already a ground wire coming from the Main Service - a 277/480V 3-ph Power Panel located in electrical room. This ground wire is already bonded and grounded (earthed) to a grounding electrode inside the electrical room.
Do we still need to ground (earth) the transformer secondary again to an acceptable grounding electrode?
In the example below in which the Delta-Wye transformer is installed in a tenant space. There is already a ground wire coming from the Main Service - a 277/480V 3-ph Power Panel located in electrical room. This ground wire is already bonded and grounded (earthed) to a grounding electrode inside the electrical room.
Do we still need to ground (earth) the transformer secondary again to an acceptable grounding electrode?