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inear foot shall be included for a show window, measured horizontally along its base. Informational Note: See 220.14(G) for branch circuits supplying show windows. (B) Track Lighting. For track lighting in other than dwelling units or guest rooms or guest suites of hotels or motels, an additional lo...

inear foot shall be included for a show window, measured horizontally along its base. Informational Note: See 220.14(G) for branch circuits supplying show windows. (B) Track Lighting. For track lighting in other than dwelling units or guest rooms or guest suites of hotels or motels, an additional load of 150 volt-amperes shall be included for every 600 mm (2 ft) of lighting track or fraction thereof. Where multicircuit track is installed, the load shall be considered to be divided equally between the track circuits. Exception: If the track lighting is supplied through a device that limits the current to the track, the load shall be permitted to be calculated based on the rating of the device used to limit the current. ENHANCED CONTENT Collapse Section 220.46(B) is not intended to limit the number of feet of track on a single branch circuit, nor is it intended to limit the number of fixtures on an individual track. It is meant to be used solely for load calculations of feeders and services. Exception. The rating of the branch-circuit OCPD can be used for this calculation, or the device used to limit current can be a supplementary OCPD. This exception enables load calculations to be more in line with the limitations placed on building lighting loads by energy codes. 220.47 Receptacle Loads - Other Than Dwelling Units. Receptacle loads calculated in accordance with 220.14(H) and (I) shall be permitted to be made subject to the demand factors given in Table 220.45 or Table 220.47. Table 220.47 Demand Factors for Non-Dwelling Receptacle Loads Portion of Receptacle Load to Which Demand Factor Applies (Volt-Amperes) Demand Factor (%) First 10 kVA or less at 100 Remainder over 10 kVA at 50 220.50 Motors and Air-Conditioning Equipment. (A) Motors. The conductor sizing requirements specified in 430.24 and 430.25 and the feeder demand factor calculation method specified in 430.26 shall be used to determine motor loads. (B) Air-Conditioning Equipment. The conductor sizing requirements specified in Part IV of Article 440 shall be used to determine air-conditioning loads for hermetic refrigerant motor- compressors. 220.51 Fixed Electric Space Heating. Fixed electric space-heating loads shall be calculated at 100 percent of the total connected load. However, in no case shall a feeder or service load current rating be less than the rating of the largest branch circuit supplied. Exception: If reduced loading of the conductors results from units operating on duty- cycleor intermittently, or from all units not operating at the same time, the authority having jurisdiction shall be permitted to grant permission for feeder and service conductors to have an ampacity less than 100 percent if the conductors have an ampacity for the load so determined. 220.52 Small-Appliance and Laundry Loads - Dwelling Unit. (A) Small-Appliance Circuit Load. In each dwelling unit, the load shall be calculated at 1500 volt-amperes for each 2-wire small-appliance branch circuit as covered by 210.11(C)(1). Where the load is subdivided through two or more feeders, the calculated load for each shall include not less than 1500 volt-amperes for each 2-wire small- appliance branch circuit. These loads shall be permitted to be included with the general lighting load and subjected to the demand factors provided in Table 220.45. Exception: The individual branch circuit permitted by 210.52(B)(1), Exception No. 2, shall be permitted to be excluded from the calculation required by 220.52. (B) Laundry Circuit Load. A load of not less than 1500 volt-amperes shall be included for each 2-wire laundry branch circuit installed as covered by 210.11(C)(2). This load shall be permitted to be included with the general lighting load and shall be subjected to the demand factors provided in Table 220.45. ENHANCED CONTENT Collapse Where additional small-appliance and laundry branch circuits are provided, they also are calculated at 1500 volt-amperes per circuit. All small appliance and laundry loads are combined with the general lighting load, and the demand factors in Table 220.45 can be applied. 220.53 Appliance Load - Dwelling Unit(s). Applying a demand factor of 75 percent to the nameplate rating load of four or more appliances rated 1/4 hp or greater, or 500 watts or greater, that are fastened in place, and that are served by the same feeder or service in a one- family, two-family, or multifamily dwelling shall be permitted. This demand factor shall not apply to the following: * (1) Household electric cooking equipment that is fastened in place * (2) Clothes dryers * (3) Space heating equipment * (4) Air-conditioning equipment * (5) Electric vehicle supply equipment (EVSE) ENHANCED CONTENT Collapse For appliances fastened in place (other than ranges and other cooking appliances, clothes dryers, space-heating, air-conditioning equipment, and electric vehicle supply equipment), feeder capacity must be provided for the sum of these loads. If the total load includes four or more such appliances, a demand factor of 75 percent is permitted. To reduce the number of small motor-operated appliance loads (e.g., bathroom ventilating fans) that are typically supplied by general-purpose branch circuits from having two demand factors applied (220.53 plus Table 220.45), the minimum appliance rating that can be considered in applying the 75 percent demand of 220.53 is either 500 watts or greater or 1/4 horsepower. See also Table 430.248 in Part XIV of Article 430 for the full-load current, in amperes, for single-phase ac motors in accordance with 220.50. 220.54 Electric Clothes Dryers - Dwelling Unit(s). The load for household electric clothes dryers in a dwelling unit(s) shall be either 5000 watts (volt-amperes) or the nameplate rating, whichever is larger, for each dryer served. The use of the demand factors in Table 220.54 shall be permitted. Where two or more single-phase dryers are supplied by a 3-phase, 4-wire feeder or service, the total load shall be calculated on the basis of twice the maximum number connected between any two phases. Kilovolt-amperes (kVA) shall be considered equivalent to kilowatts (kW) for loads calculated in this section. Table 220.54 Demand Factors for Household Electric Clothes Dryers Number of Dryers Demand Factor (%) 1-4 100 5 85 6 75 7 65 8 60 9 55 10 50 11 47 12-23 47% minus 1% for each dryer exceeding 11 24-42 35% minus 0.5% for each dryer exceeding 23 43 and over 25% ENHANCED CONTENT Collapse The use of demand factors is permitted but not required, because the NEC does not prohibit applying the full load of all dryers to a service and/or feeder calculation. However, this method is not necessary or practical, and experience has demonstrated that the use of the Table 220.54 demand factors provides sufficient capacity in the service for dryer loads. It is unlikely that all dryers will be in operation simultaneously, and Table 220.54 was developed based on utility demand that proves this point. The minimum load to be used is the larger of 5000 volt-amperes or the nameplate rating of the dryer. In the following calculation example, the nameplate rating of 5500 watts (VA) is used. In addition, because of the supply system characteristics, calculation is a little different from simply adding the total rating of all dryers and applying the appropriate demand factor. The load of 10 single-phase dryers will be distributed across a 3-phase supply system. If the service and feeder load for this multifamily dwelling is calculated using the optional calculation for multifamily dwellings from Part IV of Article 220, the dryer load is not subject to an individual demand factor as required by the Part III calculation. The total connected load is subjected to a single demand factor from Table 220.84(B) based on the total number of dwelling units served by a set of service or feeder conductors. For a set of conductors serving 10 dwelling units, the demand factor is 43 percent. The optional calculation can be used if all the conditions specified in 220.84(A)(1) through (A)(3) are met. Otherwise, the calculation for the multifamily dwelling must be performed in accordance with the requirements of Part III of Article 220. 220.55 Electric Cooking Appliances in Dwelling Units and Household Cooking Appliances Used in Instructional Programs. The load for household electric ranges, wall-mounted ovens, counter-mounted cooking units, and other household cooking appliances individually rated in excess of 13/4 kW shall be permitted to be calculated in accordance with Table 220.55. Kilovolt-amperes (kVA) shall be considered equivalent to kilowatts (kW) for loads calculated under this section. Where two or more single-phase ranges are supplied by a 3-?phase, 4-wire feeder or service, the total load shall be calculated on the basis of twice the maximum number connected between any two phases. Table 220.55 Demand Factors and Loads for Household Electric Ranges, Wall-Mounted Ovens, Counter-Mounted Cooking Units, and Other Household Cooking Appliances over 13/4 kW Rating (Column C to be used in all cases except as otherwise permitted in Note 3.) Number of Appliances Demand Factor (%) (See Notes) Column C Maximum Demand (kW) (See Notes) (Not over 12 kW Rating) Column A (Less than 31/2 kW Rating) Column B (31/2 kW through 83/4 kW Rating) 1 80 80 8 2 75 65 11 3 70 55 14 4 66 50 17 5 62 45 20 6 59 43 21 7 56 40 22 8 53 36 23 9 51 35 24 10 49 34 25 11 47 32 26 12 45 32 27 13 43 32 28 14 41 32 29 15 40 32 30 16 39 28 31 17 38 28 32 18 37 28 33 19 36 28 34 20 35 28 35 21 34 26 36 22 33 26 37 23 32 26 38 24 31 26 39 25 30 26 40 26-30 30 24 15 kW + 1 kW for each range 31-40 30 22 41-50 30 20 25 kW + 3/4 kW for each range 51-60 30 18 61 and over 30 16 Notes: 1. Over 12 kW through 27 kW ranges all of same rating. For ranges individually rated more than 12 kW but not more than 27 kW, the maximum demand in Column C shall be increased 5 percent for each additional kilowatt of rating or major fraction thereof by which the rating of individual ranges exceeds 12 kW. 2. Over 83/4 kW through 27 kW ranges of unequal ratings. For ranges individually rated more than 83/4 kW and of different ratings, but none exceeding 27 kW, an average value of rating shall be calculated by adding together the ratings of all ranges to obtain the total connected load (using 12 kW for any range rated less than 12 kW) and dividing by the total number of ranges. Then the maximum demand in Column C shall be increased 5 percent for each kilowatt or major fraction thereof by which this average value exceeds 12 kW. 3. Over 13/4 kW through 83/4 kW. In lieu of the method provided in Column C, adding the nameplate ratings of all household cooking appliances rated more than 13/4 kW but not more than 83/4 kW and multiplying the sum by the demand factors specified in Column A or Column B for the given number of appliances shall be permitted. Where the rating of cooking appliances falls under both Column A and Column B, the demand factors for each column shall be applied to the appliances for that column, and the results added together. 4. Calculating the branch-circuit load for one range in accordance with Table 220.55 shall be permitted. 5. The branch-circuit load for one wall-mounted oven or one counter-mounted cooking unit shall be the nameplate rating of the appliance. 6. The branch-circuit load for a counter-mounted cooking unit and not more than two wall-mounted ovens, all supplied from a single branch circuit and located in the same room, shall be calculated by adding the nameplate rating of the individual appliances and treating this total as equivalent to one range. 7. This table shall also apply to household cooking appliances rated over 13/4 kW and used in instructional programs. Informational Note No. 1: See Informative Annex D for examples. Informational Note No. 2: See Table 220.56 for demand factors for commercial cooking equipment. ENHANCED CONTENT Collapse The demand factors are based on the diversified use of household appliances, because it is unlikely that all appliances will be used simultaneously or that all cooking elements and the oven of a range will be at maximum heat for any length of time. The values in Column C are applicable to installations where all ranges in the group have the same rating. Note 1 applies where the ranges are rated greater than 12 kilowatts, and Note 2 applies where the ranges in a group have different ratings. Column C must be used unless Note 3 is applicable. Notes 3 and 4 cover installations where the circuit supplies multiple cooking components, which are combined and treated as a single range. Table Note 1. For household electric ranges, the size of the conductors must be determined by the rating of the range. According to Table 220.55, for one range rated 12 kilowatts or less, the maximum demand load is 8 kilowatts. Note that 210.19(C) does not permit the branch-circuit rating of a circuit supplying household ranges with a nameplate rating of 83/4 kilowatts to be less than 40 amperes. The demand in Column C must be increased if an individual range is rated over 12 kilowatts but not more than 27 kilowatts. All ranges in the group must have the same rating to apply Note 1. If the ratings are different, refer to Note 2. Table Note 2. If ranges in a group installation have different ratings over 83/4 kilowatts through 27 kilowatts, the ratings are added together to determine the average rating and the maximum demand. The demand in Column C must be increased if the average rating is over 12 kilowatts. If the ratings are the same, refer to Note 1. Table Note 3. For a group installation of ranges with ratings over 13/4 kilowatts through 83/4 kilowatts, the ratings are permitted to be added together for determining a demand factor. Ranges rated below 31/2 kilowatts should be grouped independently of those rated 31/2 kilowatts and above. The appropriate column (A or B) is used rather than Column C. Table Note 4. The branch-circuit load for one range is permitted to be computed by using either the nameplate rating of the appliance or Table 220.55. A counter-mounted cooking appliance has a smaller load rating than does a full-sized range with an oven. If a single branch circuit supplies a counter-mounted cooking unit and not more than two wall-mounted ovens, all of which are located in the same room, the nameplate ratings of the appliances can be added, and the total treated as the equivalent of one range. For feeder demand factors other than dwelling units (commercial electric cooking equipment, dishwasher booster heaters, water heaters, etc.), see Table 220.56. Where a counter-mounted cooking appliance like the one illustrated below is used with a separate wall oven, it is permissible to run a single branch circuit to the kitchen and supply each with branch-circuit tap conductors installed as specified in 210.19(C), Exception No. 1. 220.56 Kitchen Equipment - Other Than Dwelling Unit(s). Calculating the load for commercial electric cooking equipment, dishwasher booster heaters, water heaters, and other kitchen equipment in accordance with Table 220.56 shall be permitted. Other kitchen equipment shall include equipment that is fastened in place and rated 1/4 hp or greater, or 500 watts or greater. These demand factors shall be applied to all equipment that has either thermostatic control or intermittent use as kitchen equipment. These demand factors shall not apply to space-heating, ventilating, or air- conditioning equipment. However, in no case shall the feeder or service calculated load be less than the sum of the largest two kitchen equipment loads. Table 220.56 Demand Factors for Kitchen Equipment - Other Than Dwelling Unit(s) Number of Units of Equipment Demand Factor (%) 1 100 2 100 3 90 4 80 5 70 6 and over 65 ENHANCED CONTENT Collapse The demand factors in Table 220.56 can be applied to a combination of cooking, dishwashing, water heating, and other types of commercial kitchen appliances, and the combined total allows a deeper demand factor to be applied. Thermostatically controlled electric cooking appliances are permitted, but not required, to have the demand applied to the appliance nameplate rating. Because commercial electric cooking appliances are used more intensively and for longer periods, the demand factors for commercial applications are not as generous as those permitted for dwelling units. The applications of the demand factors in 220.55 are permitted to be used for household cooking equipment used in instructional programs, such as in culinary schools, because the equipment is not subjected to the continuous demands that would exist in a commercial restaurant. 220.57 Electric Vehicle Supply Equipment (EVSE) Load. The EVSE load shall be calculated at either 7200 watts (volt-amperes) or the nameplate rating of the equipment, whichever is larger. 220.60 Noncoincident Loads. If it is unlikely that two or more noncoincident loads will be in use simultaneously, using only the largest load(s) that will be used at one time for calculating the total load of a feeder or service shall be permitted. If a motor or air-conditioning load is part of the noncoincident load and is not the largest of the noncoincident loads, 125 percent of either the motor load or air- conditioning load, whichever is larger, shall be used in the calculation. 220.61 Feeder or Service Neutral Load. (A) Basic Calculation. The feeder or service neutral load shall be the maximum unbalance of the load determined by this article. The maximum unbalanced load shall be the maximum net calculated load between the neutral conductor and any one ungrounded conductor. Exception: For 3-wire, 2-phase or 5-wire, 2-phase systems, the maximum unbalanced load shall be the maximum net calculated load between the neutral conductor and any one ungrounded conductor multiplied by 140 percent. (B) Permitted Reductions. A service or feeder supplying the following loads shall be permitted to have an additional demand factor of 70 percent applied to the amount in 220.61(B)(1) and a portion of the amount in 220.61(B)(2). (1) Household Electric Ranges, Wall-Mounted Ovens, Counter-Mounted Cooking Units, and Dryers. A feeder or service supplying household electric ranges, wall-mounted ovens, counter-mounted cooking units, and electric dryers, where the maximum unbalanced load has been determined in accordance with Table 220.55 for ranges and Table 220.54 for dryers. (2) Unbalanced Load in Excess of 200 Amperes. That portion of the unbalanced load in excess of 200 amperes where the feeder or service is supplied from a 3-wire dc or single-phase ac system; a 4- wire, 3-phase system; a 3-wire, 2-phase system; or a 5-wire, 2-phase system. Informational Note: See Informative Annex D, Examples D1(a), D1(b), D2(b), D4(a), and D5(a) for examples of unbalanced feeder or service neutral loads. (C) Prohibited Reductions. There shall be no reduction of the neutral or grounded conductor capacity applied to the amount in 220.61(C)(1), or portion of the amount in (C)(2), from that determined by the basic calculation: * (1) Any portion of a 3-wire circuit consisting of 2 ungrounded conductors and the neutral conductor of a 4-wire, 3-phase, wye-connected system * (2) That portion consisting of nonlinear loads supplied from a 4-wire, wye- connected, 3-phase system Informational Note: A 3-phase, 4-wire, wye-connected power system used to supply power to nonlinear loads might necessitate that the power system design allows for the possibility of high harmonic neutral conductor currents. ENHANCED CONTENT Collapse Section 220.61 describes the basis for calculating the neutral load of feeders or services as the maximum unbalanced load that can can occur between the neutral and any ungrounded conductor. For a household electric range or clothes dryer, the maximum unbalanced load for a single-phase feeder or service can be assumed to be 70 percent, so the neutral can be sized on that basis. If the unbalanced load exceeds 200 amperes, 220.61(B) permits the reduction of the feeder neutral conductor size under specific conditions of use. However, 220.61(C)(1) and (C)(2) cite a circuit arrangement and a load characteristic as applications where the capacity of a neutral or grounded conductor of a feeder or service is not permitted to be reduced. The neutral is considered a current-carrying conductor if the load of the electric-discharge lighting, data-processing, or similar equipment on the feeder neutral consists of more than half the total load, in accordance with 310.15(E)(3). Electric-discharge lighting and data-processing equipment could have harmonic currents in the neutral that might exceed the load current in the ungrounded conductors. The Informational Note to item (2) cautions designers and installers to be aware of harmonic contribution and to design the electrical installation to accommodate the harmonic load imposed on neutral conductors. In some instances, the neutral current could exceed the current in the phase conductors. A 3-phase, 4-wire (208Y/120-volt or 480Y/277-volt) system is often used to supply both lighting and motor loads. The 3-phase motor loads are balanced loads that are not connected to the neutral and, thus, would not be considered when determining the maximum unbalanced load. The maximum current on the neutral is due to lighting loads or circuits that are connected lineto- neutral. On this type of system (3-phase, 4-wire), a demand factor of 70 percent is permitted by 220.61(B) for that portion of the neutral load more than 200 amperes. For example, if the maximum possible unbalanced load is 500 amperes, the neutral would have to be large enough to carry 410 amperes (200 amperes plus 70 percent of 300 amperes, or 410 amperes). The 70 percent demand cannot be applied for that portion of the line-to-neutral load consisting of electric-discharge lighting. Section 310.15(C)(1) specifies that a neutral conductor must be counted as a current-carrying conductor if the load it serves consists of harmonic currents. The maximum unbalanced load for feeders supplying clothes dryers, household ranges, wall-mounted ovens, and counter-mounted cooking units is required to be considered 70 percent of the load on the ungrounded conductors. See also 220.61(B) for other systems in which the 70-percent demand factor can be applied. For examples of one-family dwelling calculations, see Examples D1(a) through D5(b) of Informative Annex D. 220.70 Energy Management Systems (EMSs). If an energy management system (EMS) is used to limit the current to a feeder or service in accordance with 750.30, a single value equal to the maximum ampere setpoint of the EMS shall be permitted to be used in load calculations for the feeder or service. The setpoint value of the EMS shall be considered a continuous load for the purposes of load calculations. Part IV. Optional Feeder and Service Load Calculations 220.80 General. Optional feeder and service load calculations shall be permitted in accordance with Part IV. 220.82 Dwelling Unit. (A) Feeder and Service Load. This section applies to a dwelling unit having the total connected load served by a single 120/240-volt or 208Y/120-volt set of 3-wire service or feeder conductors with an ampacity of 100 or greater. It shall be permissible to calculate the feeder and service loads in accordance with this section instead of the method specified in Part III of this article. The calculated load shall be the result of adding the loads from 220.82(B) and (C). Feeder and service- entrance conductors whose calculated load is determined by this optional calculation shall be permitted to have the neutral load determined by 220.61. ENHANCED CONTENT Collapse This optional calculation method applies to a single dwelling unit, whether a separate building or located in a multifamily dwelling. For examples of the optional calculations for a dwelling unit, see Examples D2(a), D2(b), D2(c), and D4(b) in Informative Annex D. (B) General Loads. The general calculated load shall be not less than 100 percent of the first 1