If the clearances specified in PSC 114.317 cannot be obtained, a fire-resistant barrier may be constructed in lieu of the required separation. The following methods of construction are acceptable:

1. Noncombustible Walls

The barrier shall extend to a projection line from the corner of the padmounted transformer to the furthest corner of the window, door or opening in question. The height of the barrier shall be 0.3 m (1 ft) above the top of the padmounted transformer. See Figure PSC 114-317D1.

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Figure PSC 114-317D1.

2. Combustible Walls

The barrier shall extend 0.9 m (3 ft) beyond each side of the padmounted transformer. The height of the barrier shall be 0.3 m (1 ft) above the top of the transformer. See Figure PSC 114-317D2.

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Figure PSC 114-317D2.

E. Fire Escapes

1. Padmounted oil-insulated transformers shall not be located within a zone extending 6.1 m (20 ft) outward and 3 m (10 ft) to either side of the point where a fire escape meets the ground. See Figure PSC 114-317E1.

2. Padmounted oil-insulated transformers located beneath fire escapes shall have a vertical clearance of not less than 3 m (10 ft) from the top of the transformer to the bottom of the fire escape. See Figure PSC 114-317E2.

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Figure PSC 114-317E1

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Figure PSC 114-317E2

PSC 114.317 History 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 35. Direct-Buried Cable

PSC 114.350 PSC 114.350 General. [NESC 350F, p. 263] (Change) Change paragraph F to read:

F. All direct-buried jacketed supply cable meeting Rule 350B and all direct-buried communication cables shall be legibly marked as follows:

The appropriate identification symbol shown in Fig 350-1 shall be indented or embossed in the outermost cable jacket at a spacing of not more than 1m (40 in). The symbol may be separate or sequentially combined with other data, or symbols, or both, printed on the jacket. If the symbol is sequentially combined, it shall be separated as indicated in Fig 350-1. If optional supplemental striping is used, only supply cables or non-metallic duct containing or intended to contain supply cables may have three equally separated longitudinal red stripes.

This rule applies to cable installed on or after January 1, 1996.

PSC 114.350 Note Exception 1: Cables with jackets that cannot be effectively marked in accordance with Rules 350F need not be marked.

PSC 114.350 Note Exception 2: Unmarked cable from stock existing prior to 1 January 1996 may be used to repair unmarked direct-buried jacketed supply cables and communication cables.

PSC 114.350 History 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 114.350 renum. from PSC 114.350F 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 114.352 PSC 114.352 Installation. Table PSC 114.352-1 [NESC Table 352-1, p. 266] Supply cable, conductor, or duct burial depth (Change and Addition)

PSC 114.352(1) (1) Change the present “Exception” after the table to “Exception 1”.

PSC 114.352(2) (2) Add a new Exception 2 as follows:

PSC 114.352 Note Exception 2: Installations of insulated secondary underground cables operating at less than 600 volts between conductors shall be permitted to be laid on the ground during winter months provided they are suitably protected.