PSC 114.094 HistoryHistory: 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; CR 18-007: consol. (intro.) and (1), renum. to PSC 114.094 and am. Register February 2020 No. 770, eff. 3-1-20.

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.

PSC 114.096 NoteException 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.”

PSC 114.096 NoteException 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 092B2 are met.

PSC 114.096 NoteRecommendation: This rule may be applied to shield wire(s) grounded at the source and which meet the multi-grounded requirements of this rule.

PSC 114.096 NoteNote 2: 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.

PSC 114.096 HistoryHistory: 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; CR 18-007: am. (intro.) Register February 2020 No. 770, eff. 3-1-20.

C. Primary and secondary circuits utilizing a single conductor as a common neutral shall have at least nine ground connections on such conductor in each 1.6 km (1 mi) of line, including those grounds at transformer locations, but not including ground connections at customers’ service equipment.

PSC 114.097 NoteException: Where it is necessary to separate the neutrals, interconnection of the neutrals shall be made through an electronic switching device designed for the purpose and of a type acceptable to the authority having jurisdiction. The device shall have a 60 Hz breakdown voltage not exceeding 3 kV and have a short circuit current withstand capability greater than the short circuit current available at the location of installation. At least one other grounding connection on the secondary neutral shall be provided in addition to the customer’s grounds at each service entrance. A distance of not less than 3.60 m (12 ft) nor more than 6.1 m (20 ft.) shall separate the secondary neutral grounding electrode from the primary neutral and surge arrester grounding electrode, which shall not be relocated to accommodate this separation. Since a difference of potential will exist where primary and secondary neutrals are not directly interconnected, the primary and secondary grounding conductors shall be insulated for 600 V.

PSC 114.097 HistoryHistory: 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; CR 18-007: am. (intro.), (1) (intro.), (2) (intro.) Register February 2020 No. 770, eff. 3-1-20.

A bond not smaller than AWG No. 6 copper or equivalent shall be placed between the communication grounding electrode and the supply system neutral grounding electrode where separate electrodes are used at the structure or building being served. All separate electrodes shall be bonded together except where separation is required per Rule 097. Bonding to other systems shall not be done on or within a metering enclosure unless a means of bonding, intended for inter-system bonding, is furnished as part of the metering enclosure.

PSC 114.099 NoteRecommendation: If water piping is used as a bonding means, care must be taken to assure that the metallic path is continuous between electrodes.

PSC 114.099 NoteNote 1: See NEC Article 800-100(D) for corresponding NEC requirements.

PSC 114.099 NoteNote 2: The bonding together of all separate electrodes limits potential differences between them and between their associated wiring systems.

PSC 114.099(3)(3) Transmission shield wire systems and transmission systems with under-built multi-grounded distribution systems. [Follows NESC 099C, p. 37] (Addition) Following NESC 099C, add paragraph D to read:

1. The shield wire system providing lightning protection for transmission lines (69 kV phase-to-phase and greater) shall be connected to a made or existing grounding electrode at every transmission pole or structure for each shield wire.

(a) If the transmission line has any under-built distribution attached to the same pole or structure, the shield wire system shall be bonded to the grounding conductor of the distribution neutral at each pole or structure.