Wisconsin Legislature: PSC 114.005(8)

Subchapter II — General Requirements

PSC 114.004 General requirements.

(1) Character of construction, maintenance and operation. All electrical power and communication equipment and lines shall be of such construction, and so installed, operated, and maintained as to minimize the loss of life and fire hazard.

(2) Construction, inspection and repairs.

(a) All construction and equipment shall be cleaned when necessary and inspected at such intervals as experience has shown to be necessary. Any equipment or construction known to be defective so as to endanger life or property shall be promptly repaired, permanently disconnected, or isolated until repairs can be made. Construction, repairs, additions and changes to electrical equipment and conductors shall be made by qualified persons only.

(b) Facilities installed or used in the generation, transmission, distribution, and utilization of electricity shall be designed for such installation or use.

History: 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.

PSC 114.005 Application of rules.

(1) New installations and extensions.

(a) This chapter shall apply in full to all new installations, reconstructions, alterations and extensions, except as modified or waived by the commission under par. (b).

(b) Waiving rules. The commission may modify or waive these rules in particular cases when rules are shown for any reason to be impractical or if equivalent safety is secured in other ways.

(2) Existing installations.

(a) Where an existing installation meets, or is altered to meet these rules, such installation is considered to be in compliance with this edition and is not required to comply with any previous edition.

(b) Existing installations, including maintenance replacements, which comply with prior editions of the code, need not be modified to comply with these rules except as may be directed for safety reasons by the commission and within the time the commission determines.

(c) Where a utility adds, alters, or replaces conductors or equipment on an existing structure, the structure or the facilities on the structure need not be modified or replaced if the resulting installation will be in compliance with the rules in effect at one of the following times:

1. At the time of the original installation.

2. At the time of an addition, alteration, or replacement.

3. Currently, in accordance with par. (a).

(4) Temporary installations. Modifying or waiving certain of the rules will sometimes be necessary in case of temporary installations or installations which are shortly to be dismantled or reconstructed. Such temporary construction may be used for a reasonable length of time without fully complying with this code, provided it is under competent supervision while it or adjoining equipment is energized or if it is protected by suitable barriers or warning signs when accessible to any person; but all such construction shall be made reasonably safe.

(5) Testing. Rooms which are used exclusively for routine or special electrical test work, and therefore are under the supervision of a qualified person, need comply with this code only insofar as is practical for the character of the testing done.

(6) Emergency. In case of emergency the person responsible for the installation may modify or waive any requirement of this chapter, subject to review by the commission, even should an application be pending before the commission for a requested emergency related modification or waiver.

(7) Intent.

(a) The word “shall” indicates provisions that are mandatory.

(b) The word “should” indicates provisions that are normally and generally practical for the specified conditions. However, where the word “should” is used, it is recognized that, in certain instances, additional local conditions not specified herein may make these provisions impractical. When this occurs, the difference in conditions shall be appropriately recognized and s. PSC 114.002 shall be met.

(d) Exceptions to a rule have the same force and effect required or allowed by the rule to which the exception applies.

(e) The word “RECOMMENDATION” indicates provisions considered desirable, but that are not intended to be mandatory.

(f) The word “NOTE” or the word “EXAMPLE” used in a rule indicates material provided for information or illustrative purposes only. “NOTES” and “EXAMPLES” are not mandatory and are not considered to be a part of Code requirements.

(g) A “RECOMMENDATION,” “EXCEPTION,” or “NOTE” applies to all text in that rule above its location that is indented to the same level.

(8) Applications not specifically addressed. For all applications not specifically addressed in these rules, the design, construction, operations, and maintenance shall be done in accordance with accepted good practice for the given local conditions known at the time.

History: CR 07-021: cr. Register January 2008 No. 625, eff. 2-1-08; CR13-039: r. and recr. Register June 2014 No. 702, eff. 7-1-14.

PSC 114.006 Adoption of standard by reference.

(1) Adoption of standard. The National Electrical Safety Code-2017 edition (also American National Standards Institute C2-2017 edition) subject to omissions, changes and additions as otherwise shown in this chapter, is hereby incorporated by reference into the Wisconsin State Electrical Code, Volume 1. Interim amendments to the NESC-2017 will not be effective in this state until such time as this chapter is revised to reflect such changes.

(2) Consent to incorporate NESC-2017 by reference. Pursuant to s. 227.21, Stats., the attorney general has consented to the incorporation by reference of these standards contained in the NESC-2017, except for the omissions, changes and additions as shown later in this chapter. Copies of the NESC-2017 are on file in the offices of the commission and the legislative reference bureau.

History: 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. Register February 2020 No. 770, eff. 3-1-20.

Subchapter III — Omissions, Changes or Additions to NESC-2017

PSC 114.007 Omissions, changes, additions to NESC-2017. Omissions, changes, or additions to the NESC-2017 are specified in this subchapter and are rules of the commission and not requirements of the NESC-2017.

Note 1: Each omission, change or addition is found in the same location in this subchapter as the appropriate NESC part, section or subsection where the affected rule is found. Each change or addition has been prefixed by ch. PSC 114. Following the PSC designation is the referenced NESC section or subsection and the page on which it is found in the NESC. Example: PSC 114.096C [NESC 096C, p. 34]. The word “Change” following the section number and heading means that the corresponding wording of the NESC-2017 has been changed and that the new wording is substituted at the appropriate location. The word “Addition” following the section number and heading means that a new requirement is incorporated in the NESC-2017 and that the new requirement is inserted at the appropriate location.

Note 2: To observe federal directives and recommendations that national standards adopt the metric system for units of measure, the numerical values of the NESC-2017 are stated in the metric system and in the customary inch-foot-pound system. To conform to this more international convention, this revision of the Wisconsin State Electrical Code, Volume 1 also adopts the same measurement convention. In the text, the metric value is now shown first with the customary inch-foot-pound value (in parentheses) following. In tables, the metric values are also given first and where the entire tables are duplicated, the table of metric values appears first with the table of inch-foot-pound values following.

History: 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. Register February 2020 No. 770, eff. 3-1-20.

Section 1. Introduction to the National
Electrical Safety Code

PSC 114.010 Omissions. [NESC 010 through 016, pp. 1-6] Introduction to the National Electrical Safety Code (Section 1) (Omission) Rules 010 through 016 of the NESC-2017 are omitted and not incorporated as part of the Wisconsin State Electrical Code, Volume 1.

History: 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. Register February 2020 No. 770, eff. 3-1-20.

Section 2. Definitions of Special Terms

PSC 114.02 Definitions of special terms.

(1) Administrative authority. [NESC Section 2., p. 7] (Change) Change the definition of “Administrative Authority” to read:

Administrative authority. The authority for the enforcement of this code is vested in the commission with respect to the installation and operation of circuits or equipment by public utilities and railroads in the exercise of their functions as utilities and railroads.

(2) Commission. [NESC Section 2, p. 8] (Addition) Add the following definition:

Commission. Public service commission of Wisconsin.

History: 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. (title), r. (intro.), consol. (1) (intro.) and (a), renum. to (1) and am., consol. (2) (intro.) and (a), renum. to (2) and am. Register February 2020 No. 770, eff. 3-1-20.

Section 9. Grounding Methods for Electric Supply and Communications Facilities

PSC 114.092 Point of connection of grounding conductor.

(1) Cable with insulating jacket. [NESC 092B2b(3), p. 25] (Change) Change paragraph (3) to read:

(3) Cable with insulating jacket

Additional bonding and connections between the cable insulation shielding or sheaths and the system ground are recommended. Where uninsulated cable joints in multi-grounded shielded cable systems are exposed to contact by personnel, the shielding (including sheath or concentric neutral) at the joint shall be grounded. Accessible insulated cable joints are not required to be grounded by this rule. Where multi-grounded shielding cannot be used for electrolysis of sheath-current reasons, the shielding sheaths and splice-enclosure devices shall be insulated for the voltage that may appear on them during normal operation. Bonding transformers or reactors may be substituted for direct ground connection at one end of the cable.

(2) Current in grounding conductor. [NESC 092D, p. 26] (Change) Change paragraph D to read:

D. Current in grounding conductor

Ground connection points shall be so arranged that under normal operating circumstances there will be no objectionable flow of current over the grounding conductor. If an objectionable flow of current occurs over a grounding conductor due to the use of multi-grounds, the following options may be used:

1. Determine the source of the objectionable ground conductor current and take action necessary to reduce the current to an acceptable level at its source.

2. Subject to the approval of the commission, other effective means may be used to limit the current, but no means employed shall create a situation of excessive voltage buildup on the neutral.

The system ground of the source transformer shall not be removed.

Under normal system conditions a grounding conductor current will be considered objectionable if the electrical or communications system’s owner or operator deems such current to be objectionable, or if the presence or electrical characteristics of the grounding conductor current is in violation of rules and regulations governing the electrical system, as set forth by the commission.

The temporary currents set up under abnormal conditions while grounding conductors are performing their intended protective functions are not considered objectionable. The conductor shall have the capability of conducting anticipated fault current without thermal overloading or excessive voltage buildup. Refer to Rule 93C.

Note 2: Some amount of current will always be present on the grounding conductors of an operating AC electrical system. That current may be conducted and/or induced and is not, in and of itself, objectionable.

History: 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. PSC 114.092 (title) under s. 13.92 (4) (b) 2., Stats., renum. (1) and (2) from PSC 114.092B2b and 114.092D under s. 13.92 (4) (b) 1., Stats., Register March 2015 No. 711; CR 18-007: am. (title), (1) (intro.), (2) (intro.) Register February 2020 No. 770, eff. 3-1-20.

PSC 114.094 Grounding electrodes. [NESC 094B3, p. 32] (Omission) Rule 094B3 of the NESC-2017 is omitted and not incorporated as part of the Wisconsin State Electrical Code, Volume 1.

History: 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.

PSC 114.096 Ground resistance requirements. [NESC 096C, p. 34] (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 092B2 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.

Note 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.

History: 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.

PSC 114.097 Separation of grounding conductors.

(1) Paragraph C. [NESC 097C, p. 35] (Changes) Change paragraph C to read:

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.

(2) Underground or single-grounded systems and multi-grounded systems. [NESC 097D, p. 35] (Change) Change paragraph D to read:

D. Multi-grounded systems

On multi-grounded systems, the primary and secondary neutrals shall be interconnected according to Rule 097B.

Exception: 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.

Note 2: Cooperation of all communications and supply utilities, customers of these utilities, and others may be necessary to obtain effective isolation between primary and secondary neutrals.

History: 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.

PSC 114.099 Additional requirements for grounding and bonding of communication apparatus.

(1) Additional requirements for grounding and bonding of communication apparatus. [NESC 099, p. 36] (Change) Change title to read:

(2) Bonding of electrodes. [NESC 099C, p. 37] (Change) Change paragraph C to read:

C. Bonding of electrodes

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.