Section 114.096. Multi-grounded systems.

  [NESC 096C, p. 32] (Change) Change paragraph C to read:

C. The neutral, which shall be of sufficient size and ampacity for the duty involved, shall be connected to a made or existing electrode at each transformer location and at a sufficient number of additional points with made or existing electrodes to total not less than nine grounds in each 1.6 km (1 mi) of line, including those grounds at transformer locations, but not including grounds at individual services. In rural districts, the primary neutral shall be connected to a made or existing electrode at each pole to which it is attached. For the purposes of this rule, rural districts are those areas outside of cities and villages.

Exception 1: In underground multi-grounded systems where an insulating jacket or nonmetallic conduit is used over direct-buried concentric-neutral supply cable, this requirement may be reduced to four grounds in each 1.6 km (mile). This exception for use of supply cable with an insulating jacket or nonmetallic conduit shall not be permitted for random lay construction. See Part 3, Rule 354, "Random Separation--Separation Less Than 300 mm (12 in) from Underground Structures or Other Cables."

Exception 2: Where underwater crossings are encountered, the requirements of made electrodes do not apply for the underwater portion if the neutral is of sufficient size and capacity for the duty involved and the requirements of Rule 92B2 are met.

Recommendation: This rule may be applied to shield wire(s) grounded at the source and which meet the multi-grounded requirements of this rule.

CR 07-021 : cr. Register January 2008 No. 625 , eff. 2-1-08; CR 13-039 : r. and recr. Register June 2014 No. 702 , eff. 7-1-14; renum. PSC 114.096 from PSC 114.096C under s. 13.92 (4) (b) 1. , Stats., Register March 2015 No. 711 .

Note

Multi-grounded systems extending over a substantial distance are more dependent on the multiplicity of grounding electrodes than on the resistance to ground of any individual electrode. Therefore, no specific values are imposed for the resistance of individual electrodes. Microsoft Windows NT 6.1.7601 Service Pack 1