Receptacles
Single Receptacle on an Individual Branch Circuit
A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.Total Cord-and-Plug-Connected Load
Where connected to a branch circuits supplying two or more receptacles or outlets, Receptacle shall not supply a total cord and-plug-connected load in excess of the Maximum.Table: Maximum Cord-and-Plug-Connected Load to Receptacle
Circuit
rating in (A)
|
Receptacle
rating in (A)
|
Maximum
load in (A)
|
15
or 20
|
15
|
12
|
20
|
20
|
16
|
30
|
30
|
24
|
Receptacle Ratings
Where connected to a branch circuit supplying two or more receptacles or outlets, receptacle ratings shall conform to the values listed in NEC Table210.21(B)(3), or where larger than 50 amperes, the receptacle rating shall not be less than the branch-circuit rating.Table: Receptacle Ratings for Various Size Circuits
Circuit
rating in (A)
|
Receptacle
rating in (A)
|
15
|
Not
over 15
|
20
|
15
or 20
|
30
|
30
|
40
|
40
or 50
|
50
|
50
|
A single receptacle installed on an individual
branch circuit must have an ampere rating not less than that of the branch
circuit. For example, a single receptacle on a 20-ampere individual branch
circuit must be rated at 20 amperes; however, two or more15-ampere receptacles
or duplex receptacles are permitted on a 20-ampere general purpose branch
circuit. This requirement does not apply to specific types of cord-and
plug-connected arc welders.
Branch-Circuit Requirements — Summary
Table: Summary of Branch-Circuit Requirements
Circuit rating
|
15
|
20
|
30
|
40
|
Conductor (min size)
circuit wires
|
14
|
12
|
10
|
8
|
Taps
|
14
|
14
|
14
|
12
|
Over current protection
|
15
|
20
|
30
|
40
|
Outlet devices
|
||||
Lamp holders
|
Any type
|
Any type
|
Heavy duty
|
Heavy duty
|
Receptacle rating
|
15 A max.
|
15-20 A
|
30 A
|
40 or 50 A
|
Maximum load
|
15
|
20
|
30
|
40
|
Note that the conductor size is converted to square mm in the project design to match the Egyptian market.
Dwelling Unit Receptacle Outlets
This section provides requirements for 125-volt, 15- and 20-ampere receptacle outlets .Receptacle outlets required by this section shall be in addition to any receptacle that is part of a luminaries (lighting fixture) or appliance, located within cabinets or cupboards, or located more than 1.7 m (5 1/ 2 ft) above the floor.
Dwelling unit receptacle outlets
Spacing
Receptacles shall be installed so that no point measured horizontally along the floor line in any wall space is more than 1.8 m (6 ft) from a receptacle outlet.Wall Space
As used in this section, a wall space shall include the following:-Any space 600 mm (2 ft) or more in width (including space measured around corners) and unbroken along the floor line by doorways, fireplaces, and similar openings.
-The space occupied by fixed panels in exterior walls, excluding sliding panels.-The space afforded by fixed room dividers such as freestanding bar-type counters or railings.
Wall space
Floor Receptacles
Receptacle outlets in floors shall not be counted as part of the required number of receptacle outlets unless located within 450 mm (18 in.) of the wall.Bathrooms
In dwelling units, at least one receptacle outlet shall be installed in bathrooms within 900 mm (3 ft) of the outside edge of each basin. The receptacle outlet shall be located on a wall or partition that is adjacent to the basin or basin counter-top.
Receptacle Dwelling
Hallways
In dwelling units, hallways of 3.0 m (10 ft) or more in length shall have at least one receptacle outlet. As used in this subsection, the hall length shall be considered the length along the centreline of the hall without passing through a doorway.Outdoor Outlets
For a one-family dwelling and each unit of a two-family dwelling, that is at grade level, at least one receptacle outlet accessible at grade level and not more than 2.0 m above grade shall be installed at the front and back of the dwelling.These sockets are usually protected using Ground fault circuit interrupter (GFCI) as shown in next figure.
Outdoor outlets and GFCI placed
Heating, Air-Conditioning, and Refrigeration Equipment Outlet
A 125-volt, single-phase, 15- or 20-ampere-rated receptacle outlet shall be installed at an accessible location for the servicing of heating, air-conditioning, and refrigeration equipment. The receptacle shall be located on the same level and within 7.5 m (25 ft) of the heating, air-conditioning, and refrigeration equipment. The receptacle outlet shall not be connected to the load side of the equipment disconnecting means.Receptacle Outlets
Except as covered in 220.14(J) and (K), receptacle outlets shall be calculated at not less than 180 volt-amperes for each single or for each multiple receptacle on one yoke. A single piece of equipment consisting of a multiple receptacle comprised of four or more receptacles shall be calculated at not less than 90 volt-amperes per receptacle. This provision shall not be applicable to the receptacle outlets specified in 210.11(C)(1) and (C)(2).As illustrated in Exhibit 220.3, the load of 180 volt-amperes is applied to single And multiple receptacles mounted on a single yoke or strap, and a load of 360 volt-amperes is applied to each receptacle that consists of four receptacles. These are considered receptacle outlets, in accordance with 220.14(I). The receptacle outlets are not the lighting outlets installed for general illumination or the small-appliance branch circuits, as indicated in 220.14(J). The receptacle load for outlets for general illumination in one- and two-family and multifamily dwellings and in guestrooms of hotels and motels is included in the general lighting load value assigned by Table 220.12. The load requirement for the small-appliance branch circuits is 1500 volt-amperes per circuit, as described in 220.52(A). Note in Exhibit 220.3 that the last outlet of the top circuit consists of two Duplex receptacles on separate straps. That outlet is calculated at 360 volt-amperes because each duplex receptacle is on one yoke. The multiple receptacle supplied from the bottom circuit in the exhibit, which comprises four receptacles, is calculated at 90 volt-amperes per receptacle (4 × 90 VA = 360 VA). For example, single-strap and multiple receptacledevices are calculated as follows: Device Computed Load
Duplex receptacle 180 VA
Triplex receptacle 180 VA
Double duplex receptacle 360 VA (180 × 2)
Quad or four-plex-type receptacle 360 VA (90 × 4)
Receptacle outlets
Receptacle branch circuit
Exhibit 220.4 Maximum number of outlets permitted on 15- and 20-amper branch circuits. For circuits supplying loads consisting of motor-operated utilization equipment that is fastened in place and has a motor larger than 1/ 8hp in combination with other loads, the total calculated load shall be based on 125 percent of the largest motor load plus the sum of the other loads.
Small Appliance Circuit Load
In each dwelling unit, the load shall be calculated at1500 volt-amperes for each 2-wire small-appliance branch circuit required byWhere 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 220.42.
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 appliances fastened in place (other than ranges, clothes dryers, and space-heating and air-conditioning equipment), feeder capacity must be provided for the sum of these loads; for a total load of four or more such appliances, a demand factor of 75 percent may be applied. See Table 430.248 for the full-load current, in amperes, for single phase ac motors, in accordance with 220.50.General Loads:
The general calculated load shall be not less than 100 percent of the first 10 kVA plus 40 percent of the remainder of the following loads:
-33 volt-amperes/m 2 or 3 volt-amperes/ft 2 for general lighting and general-use receptacles. The floor area for each floor shall be calculated from the outside dimensions of the dwelling unit. The calculated floor area shall not include open porches, garages, or unused or unfinished spaces not adaptable for future use.
-1500 volt-amperes for each 2-wire, 20-ampere small-appliance branch circuit and each laundry branch circuit specified in 220.
Heating and Air-Conditioning Load
The largest of the following six selections (load in kVA) shall be included:-100 percent of the nameplate rating(s) of the air conditioning and cooling.
-100 percent of the nameplate rating(s) of the heating when a heat pump is used without any supplemental electric heating.
-100 percent of the nameplate ratings of electric thermal storage and other Heating systems where the usual load is expected to be continuous at the full nameplate value. Systems qualifying under this selection shall not be calculated under any other selection in 220.82(C).
-100 percent of the nameplate rating(s) of the heat pump compressor and 65 percent of the supplemental electric heating for central electric space heating systems. If the heat pump compressor is prevented from operating at the same time as the supplementary heat, it does not need to be added to the supplementary heat for the total central space heating load.
-65 percent of the nameplate rating(s) of electric space heating if less than four separately controlled units.
-40 percent of the nameplate rating(s) of electric space heating if four or more separately controlled units.
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