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all be rated in accordance with the maximum permitted ampere rating or setting of the overcurrent device. Where conductors of higher ampacity are used for any reason, the ampere rating or setting of the specified overcurrent device shall determine the circuit rating. 235.19 Conductors - Minimum Ampa...

all be rated in accordance with the maximum permitted ampere rating or setting of the overcurrent device. Where conductors of higher ampacity are used for any reason, the ampere rating or setting of the specified overcurrent device shall determine the circuit rating. 235.19 Conductors - Minimum Ampacity and Size. The ampacity of conductors shall be in accordance with 310.14 and 315.60, as applicable. Branch-circuit conductors shall be sized in accordance with 235.19(A) or (B). (A) General. The ampacity of branch-circuit conductors shall not be less than 125 percent of the designed potential load of utilization equipment that will be operated simultaneously. (B) Supervised Installations. For supervised installations, branch-circuit conductor sizing shall be permitted to be determined by qualified persons under engineering supervision. Supervised installations are defined as those portions of a facility where both of the following conditions are met: * (1) Conditions of design and installation are provided under engineering supervision. * (2) Qualified persons with documented training and experience in over 1000-volt ac or 1500-volt dc systems provide maintenance, monitoring, and servicing of the system. 235.20 Overcurrent Protection. Branch-circuit conductors and equipment shall be protected by overcurrent protective devices that have a rating or setting that complies with 235.20(A) through (C). (A) Continuous and Noncontinuous Loads. Where a branch circuit supplies continuous loads or any combination of continuous and noncontinuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus 125 percent of the continuous load. Exception: Where the assembly, including the overcurrent devices protecting the branch circuit(s), is listed for operation at 100 percent of its rating, the ampere rating of the overcurrent device shall be permitted to be not less than the sum of the continuous load plus the noncontinuous load. (B) Conductor Protection. Conductors shall be protected in accordance with the ampacities specified in 310.14 or 315.60, as applicable. (C) Equipment. The rating or setting of the overcurrent protective device shall not exceed that specified in the applicable articles referenced in Table 240.3 for equipment. 235.22 Permissible Loads, Individual Branch Circuits. An individual branch circuit shall be permitted to supply any load for which it is rated, but in no case shall the load exceed the branch-circuit ampere rating. 235.23 Permissible Loads, Multiple-Outlet Branch Circuits. A branch circuit supplying two or more outlets or receptacles shall supply only the loads specified according to its size in accordance with 210.23(A) through (E) and as summarized in 210.24, and in no case shall the load exceed the branch-circuit ampere rating. (A) 15- and 20-Ampere Branch Circuits. A 15- or 20-ampere branch circuit shall be permitted to supply lighting outlets, lighting units, or other utilization equipment, or any combination of them, and shall comply with 235.23(A)(1) and (A)(2). (1) Cord-and-Plug-Connected Equipment Not Fastened in Place. The rating of any one cord-and-plug-connected utilization equipment not fastened in place shall not exceed 80 percent of the branch-circuit ampere rating. (2) Utilization Equipment Fastened in Place. The total rating of utilization equipment fastened in place, other than luminaires, shall not exceed 50 percent of the branch-circuit ampere rating where lighting units, cord- and-plug-connected utilization equipment not fastened in place, or both, are also supplied. (B) 30-Ampere Branch Circuits. A 30-ampere branch circuit shall be permitted to supply fixed lighting units with heavy- duty lampholders in other than a dwelling unit(s) or utilization equipment in any occupancy. The rating of any one cord-and-plug-connected utilization equipment shall not exceed 80 percent of the branch-circuit ampere rating. (C) 40- and 50-Ampere Branch Circuits. A 40- or 50-ampere branch circuit shall be permitted to supply cooking appliances that are fastened in place in any occupancy. In other than dwelling units, such circuits shall be permitted to supply fixed lighting units with heavy-duty lampholders, infrared heating units, or other utilization equipment. (D) Branch Circuits Larger Than 50 Amperes. Branch circuits larger than 50 amperes shall supply only nonlighting outlet loads. 235.63 Equipment Requiring Servicing. A 125-volt, single-phase, 15- or 20-ampere-rated receptacle outlet shall be instal?led at an accessible location within 7.5 m (25 ft) of the equipment as specified in 210.63(A) and (B). Informational Note: See 210.8(E) for requirements on GFCI protection. (A) Heating, Air-Conditioning, and Refrigeration Equipment. The required receptacle outlet shall be located on the same level as the heating, air- conditioning, and refrigeration equipment. The receptacle outlet shall not be connected to the load side of the equipment’s branch-circuit disconnecting means. Exception: A receptacle outlet shall not be required at one- and two-family dwellings for the service of evaporative coolers. (B) Other Electrical Equipment. In other than one- and two-family dwellings, a receptacle outlet shall be located as specified in 210.63(B)(1) and (B)(2). (1) Indoor Service Equipment. The required receptacle outlet shall be located within the same room or area as the service equipment. (2) Indoor Equipment Requiring Dedicated Equipment Spaces. Where equipment, other than service equipment, requires dedicated equipment space as specified in 110.26(E), the required receptacle outlet shall be located within the same room or area as the electrical equipment and shall not be connected to the load side of the equipment’s disconnecting means. Part III. Feeders 235.201 General. Part III covers the installation requirements, overcurrent protection requirements, minimum size, and ampacity of conductors for feeders over 1000 volts ac or 1500 volts dc, nominal. 235.202 Minimum Rating and Size. The ampacity of conductors shall be in accordance with 310.14 and 315.60 as applicable. Where installed, the size of the feeder-circuit grounded conductor shall not be smaller than that required by 250.122, except that 250.122(F) shall not apply where grounded conductors are run in parallel. Feeder conductors over 1000 volts shall be sized in accordance with 235.202(A), (B), or (C). (A) Feeders Supplying Transformers. The ampacity of feeder conductors shall not be less than the sum of the nameplate ratings of the transformers supplied when only transformers are supplied. (B) Feeders Supplying Transformers and Utilization Equipment. The ampacity of feeders supplying a combination of transformers and utilization equipment shall not be less than the sum of the nameplate ratings of the transformers and 125 percent of the designed potential load of the utilization equipment that will be operated simultaneously. (C) Supervised Installations. For supervised installations, feeder conductor sizing shall be permitted to be determined by qualified persons under engineering supervision in accordance with 310.14(B) or 315.60(B). Supervised installations are defined as those portions of a facility where all of the following conditions are met: * (1) Conditions of design and installation are provided under engineering supervision. * (2) Qualified persons with documented training and experience in over 1000-volt systems provide maintenance, monitoring, and servicing of the system. 235.203 Overcurrent Protection. Feeders shall be protected against overcurrent. 235.205 Diagrams of Feeders. If required by the authority having jurisdiction, a diagram showing feeder details shall be provided prior to the installation of the feeders. Such a diagram shall show the area in square feet of the building or other structure supplied by each feeder, the total calculated load before applying demand factors, the demand factors used, the calculated load after applying demand factors, and the size and type of conductors to be used. 235.206 Feeder Equipment Grounding Conductor. Where a feeder supplies branch circuits in which equipment grounding conductors are required, the feeder shall include or provide an equipment grounding conductor, to which the equipment grounding conductors of the branch circuits shall be connected. Where the feeder supplies a separate building or structure, the requirements of 250.32 shall apply. 235.212 Identification for Feeders. (A) Grounded Conductor. The grounded conductor of a feeder, if insulated, shall be identified in accordance with 200.6. (B) Equipment Grounding Conductor. The equipment grounding conductor shall be identified in accordance with 250.119. (C) Identification of Ungrounded Conductors. Ungrounded conductors shall be identified in accordance with 235.212(C)(1) or (C)(2), as applicable. (1) Feeders Supplied from More Than One Nominal Voltage System. Where the premises wiring system has feeders supplied from more than one nominal voltage system, each ungrounded conductor of a feeder shall be identified by phase or line and system at all termination, connection, and splice points in compliance with 235.212(C)(1)(a) and (C)(1)(b). * (a) Means of Identification. The means of identification shall be permitted to be by separate color coding, marking tape, tagging, or other approved means. * (b) Posting of Identification Means. The method utilized for conductors originating within each feeder panelboard or similar feeder distribution equipment shall be documented in a manner that is readily available or shall be permanently posted at each feeder panelboard or similar feeder distribution equipment. (2) Feeders Supplied from Direct-Current Systems. Where a feeder is supplied from a dc system operating at more than 1500 volts, each ungrounded conductor of 4 AWG or larger shall be identified by polarity at all termination, connection, and splice points by marking tape, tagging, or other approved means; each ungrounded conductor of 6 AWG or smaller shall be identified by polarity at all termination, connection, and splice points in compliance with 235.212(C)(2)(a) and (C)(2)(b). The identification methods utilized for conductors originating within each feeder panelboard or similar feeder distribution equipment shall be documented in a manner that is readily available or shall be permanently posted at each feeder panelboard or similar feeder distribution equipment. * (a) Positive Polarity, Sizes 6 AWG or Smaller. Where the positive polarity of a dc system does not serve as the connection for the grounded conductor, each positive ungrounded conductor shall be identified by one of the following means: o (1) A continuous red outer finish o (2) A continuous red stripe durably marked along the conductor’s entire length on insulation of a color other than green, white, gray, or black o (3) Imprinted plus signs (+) or the word POSITIVE or POS durably marked on insulation of a color other than green, white, gray, or black, and repeated at intervals not exceeding 610 mm (24 in.) in accordance with 310.8(B) o (4) An approved permanent marking means such as sleeving or shrink-tubing that is suitable for the conductor size, at all termination, connection, and splice points, with imprinted plus signs (+) or the word POSITIVE or POS durably marked on insulation of a color other than green, white, gray, or black * (b) Negative Polarity, Sizes 6 AWG or Smaller. Where the negative polarity of a dc system does not serve as the connection for the grounded conductor, each negative ungrounded conductor shall be identified by one of the following means: o (1) A continuous black outer finish o (2) A continuous black stripe durably marked along the conductor’s entire length on insulation of a color other than green, white, gray, or red o (3) Imprinted minus signs (-) or the word NEGATIVE or NEG durably marked on insulation of a color other than green, white, gray, or red, and repeated at intervals not exceeding 610 mm (24 in.) in accordance with 310.8(B) o (4) An approved permanent marking means such as sleeving or shrink-tubing that is suitable for the conductor size, at all termination, connection, and splice points, with imprinted minus signs (-) or the word NEGATIVE or NEG durably marked on insulation of a color other than green, white, gray, or red Part IV. Outside Branch Circuits and Feeders 235.301 General. Part IV covers requirements for outside branch circuits and feeders over 1000 volts ac or 1500 volts dc, nominal, that are run on or between buildings, structures, or poles on the premises; and electrical equipment and wiring for the supply of utilization equipment that is located on or attached to the outside of buildings, structures, or poles. Outside branch circuits and feeders over 1000 volts ac or 1500 volts dc, nominal, shall comply with the applicable requirements in Parts I and II of Article 225 and with Part IV of this article, which supplements or modifies those requirements. 235.306 Conductor Size and Support. For overhead spans, open individual conductors shall not be smaller than 6 AWG copper or 4 AWG aluminum where open individual conductors and 8 AWG copper or 6 AWG aluminum where in cable. 235.310 Wiring on Buildings (or Other Structures). The installation of outside wiring on surfaces of buildings (or other structures) shall be installed as provided in 305.3. 235.314 Open-Conductor Spacings. Conductors shall comply with the spacings provided in 110.36 and 495.24. 235.339 Rating of Disconnect. The feeder or branch-circuit disconnecting means shall have a rating of not less than the calculated load to be supplied, determined in accordance with Parts I and II of Article 220 for branch circuits, Part III or IV of Article 220 for feeders, or Part V of Article 220 for farm loads. 235.350 Sizing of Conductors. The sizing of conductors over 1000 volts shall be in accordance with 235.19(A) for branch circuits and 235.19(B) for feeders. 235.351 Isolating Switches. Where oil switches or air, oil, vacuum, or sulfur hexafluoride circuit breakers constitute a building disconnecting means, an isolating switch with visible break contacts and meeting the requirements of 235.404(B), (C), and (D) shall be installed on the supply side of the disconnecting means and all associated equipment. Exception: The isolating switch shall not be required where the disconnecting means is mounted on removable truck panels or switchgear units that cannot be opened unless the circuit is disconnected and that, when removed from the normal operating position, automatically disconnect the circuit breaker or switch from all energized parts. 235.352 Disconnecting Means. (A) Location. A building or structure disconnecting means shall be located in accordance with 225.31(B), or, if not readily accessible, it shall be operable by mechanical linkage from a readily accessible point. For multibuilding industrial installations under single management, it shall be permitted to be electrically operated by a readily accessible, remote-control device in a separate building or structure. (B) Type. Each building or structure disconnect shall simultaneously disconnect all ungrounded supply conductors it controls and shall have a fault-closing rating not less than the available fault current at its supply terminals. Exception: Where the individual disconnecting means consists of fused cutouts, the simultaneous disconnection of all ungrounded supply conductors shall not be required if there is a means to disconnect the load before opening the cutouts. A permanent legible sign shall be installed adjacent to the fused cutouts and shall read DISCONNECT LOAD BEFORE OPENING CUTOUTS. Where fused switches or separately mounted fuses are instal?led, the fuse characteristics shall be permitted to contribute to the fault-closing rating of the disconnecting means. ENHANCED CONTENT Collapse Where a switch is used, fuses are permitted to help with the fault-closing capability of the switch. Using fused load-break cutouts to switch sections of overhead lines and load-break elbows to switch sections of underground lines is permitted. However, the building disconnecting means must be gang-operated to simultaneously open and close all ungrounded supply conductors. Load-break elbows and fused cutouts cannot be used as the building disconnecting means. See also 235.405(B), which contains a similar requirement for services. (C) Locking. Disconnecting means shall be lockable open in accordance with 110.25. Exception: Where an individual disconnecting means consists of fused cutouts, a suitable enclosure capable of being locked and sized to contain all cutout fuse holders shall be installed at a convenient location to the fused cutouts. (D) Indicating. Disconnecting means shall clearly indicate whether they are in the open “off” or closed “on” position. (E) Uniform Position. Where disconnecting means handles are operated vertically, the “up” position of the handle shall be the “on” position. Exception: A switching device having more than one “on” position, such as a double throw switch, shall not be required to comply with this requirement. (F) Identification. Where a building or structure has any combination of feeders, branch circuits, or services passing through or supplying it, a permanent plaque or directory shall be installed at each feeder and branch-circuit disconnect location that denotes all other services, feeders, or branch circuits supplying that building or structure or passing through that building or structure and the area served by each. 235.356 Inspections and Tests. (A) Pre-Energization and Operating Tests. The complete electrical system design, including settings for protective, switching, and control circuits, shall be prepared in advance and made available on request to the authority having jurisdiction and shall be performance tested when first installed on- site. Each protective, switching, and control circuit shall be adjusted in accordance with the system design and tested by actual operation using current injection or equivalent methods as necessary to ensure that each and every such circuit operates correctly to the satisfaction of the authority having jurisdiction. ENHANCED CONTENT Collapse The AHJ must be satisfied that the performance tests demonstrate proper operation. Section 235.356(B) requires that a report of all tests performed in accordance with 235.356(A) be provided to the AHJ prior to energizing the system. Adjustments of settings must be in accordance with the electrical system design. (1) Instrument Transformers. All instrument transformers shall be tested to verify correct polarity and burden. (2) Protective Relays. Each protective relay shall be demonstrated to operate by injecting current or voltage, or both, at the associated instrument transformer output terminal and observing that the associated switching and signaling functions occur correctly and in proper time and sequence to accomplish the protective function intended. (3) Switching Circuits. Each switching circuit shall be observed to operate the associated equipment being switched. (4) Control and Signal Circuits. Each control or signal circuit shall be observed to perform its proper control function or produce a correct signal output. (5) Metering Circuits. All metering circuits shall be verified to operate correctly from voltage and current sources in a similar manner to protective relay circuits. (6) Acceptance Tests. Complete acceptance tests shall be performed, after the substation installation is completed, on all assemblies, equipment, conductors, and control and protective systems, as applicable, to verify the integrity of all the systems. (7) Relays and Metering Utilizing Phase Differences. All relays and metering that use phase differences for operation shall be verified by measuring phase angles at the relay under actual load conditions after operation commences. (B) Test Report. A test report covering the results of the tests required in 235.356(A) shall be delivered to the authority having jurisdiction prior to energization. Informational Note: See ANSI/NETA ATS, Acceptance Testing Specifications for Electrical Power Distribution Equipment and Systems, for an example of acceptance specifications. 235.360 Clearances over Roadways, Walkways, Rail, Water, and Open Land. (A) 22 kV or Less to Ground. The clearances over roadways, walkways, rail, water, and open land for conductors and live parts up to 22 kV or less to ground shall be not less than the values shown in Table 235.360(A). Table 235.360(A) Clearances over Roadways, Walkways, Rail, Water, and Open Land Clearance Location m ft Open land subject to vehicles, cultivation, or grazing 5.6 18.5 Roadways, driveways, parking lots, and alleys 5.6 18.5 Walkways 4.1 13.5 Rails 8.1 26.5 Spaces and ways for pedestrians and restricted traffic 4.4 14.5 Water areas not suitable for boating 5.2 17.0 (B) More Than 22 kV to Ground. Clearances for the categories shown in Table 235.360(A) shall be increased by 10 mm (0.4 in.) per kV, or major fraction thereof, more than 22 kV. (C) Special Cases. For special cases, such as where crossings will be made over lakes, rivers, or areas using large vehicles such as mining operations, specific designs shall be engineered considering the special circumstances and shall be approved by the authority having jurisdiction. Informational Note: See ANSI/IEEE C2-2017, National Electrical Safety Code, for additional information. 235.361 Clearances over Buildings and Other Structures. ENHANCED CONTENT Collapse These clearance requirements and specific distances over buildings and structures correlate with requirements in the National Electrical Safety Code(r) (NESC(r)). (A) 22 kV or Less to Ground. The clearances over buildings and other structures for conductors and live parts up to 22 kV or less to ground shall be not less than the values shown in Table 235.361(A). Table 235.361(A) Clearances over Buildings and Other Structures Clearance from Conductors or Live Parts from: Horizontal Vertical m ft m ft Building walls, projections, and windows 2.3 7.5 Balconies, catwalks, and similar areas accessible to people 2.3 7.5 4.1 13.5 Over or under roofs or projections not readily accessible to people - - 3.8 12.5 Over roofs accessible to vehicles but not trucks - - 4.1 13.5 Over roofs accessible to trucks - - 5.6 18.5 Other structures 2.3 7.5 More Than 22 kV to Ground. Clearances for the categories shown in Table 235.361(A) shall be increased by 10 mm (0.4 in.) per kV, or major fraction thereof, more than 22 kV. Informational Note: See ANSI/IEEE C2-2017, National Electrical Safety Code, for additional information. Part V. Services 235.401 General. Part V covers requirements for service conductors and equipment used on circuits over 1000 volts ac and 1500 volts dc, nominal, shall comply with all of the applicable requirements in Parts I through VII of Article 230 and with Part V of this article, which supplements or modifies those requirements. In no case shall the provisions of Part V apply to equipment on the supply side of the service point. ENHANCED CONTENT Collapse Only those conductors on the load side of the service-point connection are subject to the requirements of the NEC. The service point is a specific location where the supply conductors of the electric utility and the customer-owned (premises wiring) conductors connect. The following exhibit depicts an installation where the transformer and service lateral to the service point are owned by the electric utility. The transformer secondary conductors between the service point (separate connection point outside the transformer in this scenario) and the service disconnecting means at the building are underground service conductors until the point at which they enter the building. From that point to the termination in the service equipment, they are service-entrance conductors. In the installation depicted below, the service disconnecting means is located at the customer-owned transformer primary. The conductors that connect the service point (at the top of the pole), the service disconnect