20.7    Common Neutral Systems mean those electrical supply distribution systems wherein the same specially grounded conductor is utilized as a neutral conductor of primary circuits of less than 21,000 volts and secondary circuits of 0-750 volts supplied therefrom.

20.7    Common Neutral Systems mean those electrical supply distribution systems wherein the same specially grounded conductor is utilized as a neutral conductor of primary circuits of less than 22,500 21,000 volts and secondary circuits of 0-750 volts supplied therefrom.

20.7    Common Neutral Systems mean those electrical supply distribution systems wherein the same specially grounded conductor is utilized as a neutral conductor of primary circuits of less than 22,500 volts and secondary circuits of 0-750 volts supplied therefrom.