Original Version

Rule 59.4-C

59.4-C.    Transformers

Ground conductors of Transformers on common neutral systems shall conform to the requirements of Rule 59.4-A1.

On common neutral systems, each transformer installation on a branch circuit without a loop return shall be so located that there will be not less than one ground of a resistance not greater than 3 ½ ohms on each side of the transformers installation.

A transformer installation located on a grid section of a common neutral system requires no independent ground provided that there is a ground connection, having a resistance not in excess of 3 ½ ohms, to the common neutral line conductor either at the transformer pole or at an adjacent pole.

Strikeout and Underline Version

Rule 59.4-C

59.4-C.    Transformers

Ground conductors of Transformers on common neutral systems shall conform to the requirements of Rule 59.4-A1.

On common neutral systems, each with transformers installation installed on a branch circuit without a common neutral loop return, each transformer shall be so located that there will be not less than one ground of a resistance not greater than 3 ½.5 ohms on each side of the transformers installation.

A transformer installation located on a grid section of a common neutral system requires no independent ground provided that there is a ground connection, having a resistance not in excess of 3 ½.5 ohms, to the common neutral line conductor either at the transformer pole or at an adjacent pole.

Final Version

Rule 59.4-C

59.4-C.    Transformers

Ground conductors of Transformers on common neutral systems shall conform to the requirements of Rule 59.4-A1.

On common neutral systems with transformers installed on a branch circuit without a common neutral loop return, each transformer shall be so located that there will be not less than one ground of a resistance not greater than 3.5 ohms.

A transformer installation located on a grid section of a common neutral system requires no independent ground provided that there is a ground connection, having a resistance not in excess of 3.5 ohms, to the common neutral line conductor either at the transformer pole or at an adjacent pole.