ARTICLE 215 Feeders

215.4 Feeders with Common Neutral Conductor.

(A) Feeders with Common Neutral. Up to three sets of 3- wire feeders or two sets of 4-wire or 5-wire feeders shall be permitted to utilize a common neutral.

Informational Note: See Section 200.4 for common neutral.

(B) In Metal Raceway or Enclosure. Where installed in a metal raceway or other metal enclosure, all conductors of all feeders using a common neutral conductor shall be enclosed within the same raceway or other enclosure as required in 300.20.

215.13 Panelboards. Panelboards, existing or installed in an individual unit of multifamily dwellings, shall be supplied by one feeder, except by special permission from the authority having jurisdiction.

215.14 One Dwelling Unit Not to Be Supplied Through Another. Feeder conductors supplying electricity to an individual dwelling unit shall not pass through another dwelling unit.

For the purpose of this section, a dwelling unit is defined as the area between the unit floor-surface and the subfloor of the unit above. Walls between individual dwelling units may contain feeders supplying the contiguous dwelling units. Common area walls may be used for routing feeders.

ARTICLE 220

Branch-Circuit, Feeders, and Service Calculations

II. Branch-Circuit Load Calculations

220.12 Lighting Load for Specified Occupancies. A unit load of not less than that specified in Table 220.12 for occupancies specified therein shall constitute the minimum lighting load. The floor area for each floor shall be calculated from the outside dimensions of the building, dwelling unit, or other area involved. For dwelling units, the calculated floor area shall not include open porches, garages, or unused or unfinished spaces not adaptable for future use.

Informational Note: The unit values herein are based on minimum load conditions and 100 percent power factor and may not provide sufficient capacity for the installation contemplated.

((Exception: Where the building is designed and constructed

to comply with an energy code adopted by the local authority, the lighting load shall be permitted to be calculated at the values specified in the energy code where the following conditions are met:

(1) A power monitoring system is installed that will provide continuous information regarding the total general lighting load of the building.

(2) The power monitoring system will be set with alarm values to alert the building owner or manager if the lighting load exceeds the values set by the energy code. (3) The demand factors specified in 220.42 are not applied to

the general lighting load.))

Exception: When a building or structure, other than a dwelling unit, is designed and constructed in compliance with the Seattle Energy Code and the demand factors specified in 220.42 are not applied to the general lighting load, the lighting load shall be permitted to be calculated at the values specified in the Seattle Energy Code.

Informational Note: WAC 296-46B-220-012 for lighting load calculations is incorporated with edits herein as an exception.

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: ((Where reduced loading of the conductors results from units operating on duty-cycle, intermittently, or from all units not operating at the same time, the authority having jurisdiction may grant permission for feeder and

service conductors to have an ampacity less than 100 percent, provided the conductors have an ampacity for the load so determined.)) A demand factor of 75 percent of the installed heating capacity may be used in sizing service entrance and feeder equipment for dwelling, commercial and industrial occupancies when electric service is provided to four or more fixed space heaters, or electric furnaces individually controlled. These exceptions shall not apply when optional calculations allowed by Section 220.84 are used.

220.53 Appliance Load — Dwelling Unit(s). It shall be permissible to apply a demand factor of 75 percent to the nameplate rating load of four or more appliances fastened in place, other than electric ranges, clothes dryers, space- heating equipment, or air-conditioning equipment, that are served by the same feeder or service in a one-family, two- family, or multifamily dwelling. For space heating equipment, see Section 220.51.

220.57 Electric Vehicle Outlet Load. All occupancies shall provide adequate capacity to serve a demand load of one electric vehicle charging station per parking space. The demand factor for Level 2 charging stations may be calculated using Table 220.57. Demand factors for Level 3 charging systems shall be calculated at 100% of the nameplate rating.

When the size or rating of the Level 2 charging system is unknown, an amperage rating of 40 amps at a nominal voltage of 208 or 240 shall be used for the load calculations.

Informational Note 1: See also Article 625, Electric Vehicle Charging System and charging levels are found in DPD Tips 132 and 133 Installation of Electric Vehicle

(EV) Charger (Residential and Commercial respectively).

Table 220.57

Demand Factors for Level 2 Electric Vehicle Outlets

Number of Parking Spaces Demand Factor (%)

First 3 spaces 100%

Next 4 – 20 spaces 75%

Next 21-30 spaces 50%

31 spaces and remainder over

25%

ARTICLE 225

Outside Branch Circuits and Feeders

225.32 Location.

(A) Location-General. The disconnecting means shall be installed either inside or outside of the building or structure served or where the conductors pass through the building or structure. The disconnecting means shall be at a readily accessible location nearest the point of entrance of the conductors. For the purposes of this section, the requirements in 230.6 shall be utilized.

Exception No. 1: For installations under single management, where documented safe switching procedures are established and maintained for disconnection, and where the installation is monitored by qualified individuals, the disconnecting means shall be permitted to be located elsewhere on the premises.

Exception No. 2: For buildings or other structures qualifying under the provisions of Article 685, the disconnecting means shall be permitted to be located elsewhere on the premises.

Exception No. 3: For towers or poles used as lighting standards, the disconnecting means shall be permitted to be located elsewhere on the premises.

Exception No. 4: For poles or similar structures used only for support of signs installed in accordance with Article 600, the disconnecting means shall be permitted to be located elsewhere on the premises.

(B) Location of outside feeder disconnecting means. A disconnecting means must be provided to disconnect all ungrounded conductors that supply or pass through a building or structure with the following exceptions:

(1) Outside location: A feeder disconnecting means, including that required by Articles 700, 701, or 702 of this Code for a generator, is considered to be in the building if installed on the outside of the building or structure or within sight and within fifteen feet of the building or structure. The building disconnecting means may supply only one building or structure unless the secondary building(s) or structure(s) has a separate building disconnecting means meeting the requirements of this Code and this subsection. The disconnecting means must have an identification plate with at least one-half-inch high letters which identify:

(a) the building or structure served; and

(b) the disconnecting means function as the building or structure main disconnect(s).

(2) Inside location: The feeder disconnecting means may be installed anywhere inside a building or structure when

there is a feeder disconnecting means, located elsewhere on the premises, with overcurrent protection sized for the feeder conductors.

(C) A generator disconnecting means. Generator disconnecting means installed per subsection (1)(a) or (b), is not required to be suitable for use as service equipment.

Informational Note: WAC 296-46B-225.032 requirements for the location of outside feeder disconnecting means is incorporated herein.

ARTICLE 230