Article 220, Chapter 27

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Where a building is designed and constructed to comply with an energy code adopted by the local authority and specifying an overall lighting density of less than 1.20 VA per 1.20 sq ft, the unit lighting loads in Table 220.12 for office and bank areas within the building shall be permitted to be reduced by _____ VA per sq ft.

1

When calculations in Article 220 result in a fraction of an ampere that is less than _____, such fractions can be dropped.

.5

conduit with conductors or direct-burial cable installed underground

Underground Service

Not connected to ground or conductive body that extends the ground connection

Ungrounded

There shall be no reduction in the size of the neutral or grounded conductor on _____ loads supplied from a 4 wire, wye connected, three phase system.

nonlinear

the electric utility distribution has not been installed underground

overhead service mast is most commonly used in areas where

the point of connection between the facilities of the serving utility and the premises wiring

service point

Branch circuits that supply lighting units that have ballasts, transformers, autotransformers, or LED drivers shall have the calculated load based on _____ of the units, not to the total wattage of the lamps.

the total ampere rating

The minimum feeder load for show window lighting is _____ VA per linear foot.

200

Raceways on exteriors of buildings or other structures shall be arranged to drain and shall be rain tight in wet locatipns

225.22

Where exposed to the weather, raceways enclosing service- entrance conductors shall be raintight and arranged to drain

230.53

Requires that the service disconnect be installed at a readily accessible area

230.7 A 1

requires that service disconnect be installed at a readily accessible level

230.7 A 1

Requires that the service disconnecting means consist of not more than six switches or six circuit breakers mounted

230.71 A

Calls for a minimum service 100 amperes for a one-family residence

230.79 C

The feeder/service calculated load for a multifamily dwelling containing nine 12 kW ranges is _____.

24000w

Bonding all piping and metal air ducts within the premises will provide additional safety

250.104 B

Sheet metal screws have not been tested for their ability to safely carry ground-fault currents as required

250.4 A 5

Requires that metal underground water piping, the metal frame of a building, a concrete-encased electrode, a ground ring, and rod-pipe-plate electrodes be bonded together to create a grounding electrode system

250.5

States that if 4 Awg or larger ungrounded circuit conductors enter a cabinet, box enclosure or raceway

300.4 F

A dwelling unit containing two 120V laundry branch circuits has a calculated load of _____ VA for the laundry circuits.

3000

When sizing a feeder for the fixed appliance loads in dwelling units, a demand factor of 75 percent of the total nameplate ratings can be applied if there are _____ or more appliances fastened in place on the same feeder.

4

Cable must be protected against physical damage

NEC Article 230.5

Installation of service-entrance cables

NEC Article 338

For other than dwelling occupancies, banks, or office buildings, each receptacle outlet shall be calculated at not less than _____ VA.

180

For other than dwelling units or guest rooms of hotels or motels, the feeder and service calculation for track lighting shall be calculated at 150 VA for every _____ ft of lighting track or fraction thereof unless the track is supplied through a device that limits the current to the track.

2

Feeder and service loads for fixed electric space heating loads shall be calculated at _____ percent of the total connected load.

200

Under the optional method for calculating a single family dwelling service, general loads beyond the initial 10 kVA are assessed at a _____ per-cent demand factor.

40

A demand factor of _____ percent applies to a multifamily dwelling with ten units if the optional calculation method is used.

43

A dwelling unit containing three 120V small appliance branch circuits has a calculated load of _____ VA for the small appliance circuits.

4500

Where fixed multioutlet assemblies are used in other than dwelling units or the guest rooms of hotels or motels, each _____ or fraction thereof of each separate and continuous length shall be considered as one outlet of not less than 180 VA where appliances are unlikely to be used simultaneously.

5 ft

1.16

Multipliers for multiple ground rods: 2 rods

The load for electric clothes dryers in a dwelling unit shall be _____ watts or the nameplate rating, whichever is larger, per dryer.

5000

The maximum unbalanced feeder load for household electric ranges, wall mounted ovens, and counter mounted cooking units shall be considered as _____ percent of the load on the ungrounded conductors.

70

1.29

Multipliers for multiple ground rods: 3 rods

Using the standard load calculation method, the feeder demand factor for five household clothes dryers is _____ percent.

85

1.36

Multipliers for multiple ground rods: 4 rods

A: consist of service drops or service laterals B: are on property owned or leased by the electric utility for the purpose of communications, metering, generation, control, transformation, transmission or distribution C: are located in legally established easements D: are located by other written agreements

90.2 B 5 does not cover installations under the exclusive control of an electric utility where such installations

Requirements for underground services

Article 230

Connected to established electrical continuity

Bonding

A conductor to ensure the required electrical conductivity between metal parts required to be electrically connected

Bonding conductor

(Watts X hours used X cost per kWh)/ 1000

Cost

The conductive paths that provides a ground fault current path and connects normally non-current-carrying metal parts of equipment together

Equipment Grounding Conductor

The demand factors of Table 220.56 apply to space heating, ventilating, or air conditioning equipment.

F

The earth

Ground

An unintentionally, electrically conducting connection between a normally current carrying conductor of an electrical circuit

Ground fault

An electrically conductive path from the point of a ground fault on a wiring system through normally non-current carrying conductors

Ground-Fault current path

A system of circuit conductor that is intentionally grounded

Grounded conductor

A conducting object through which a direct connection to earth is established

Grounding Electrode

90 degrees

Hinged door on a panel shall open

Where it is unlikely that two or more noncoincident loads will be in use simultaneously, only the _____ the loads used at one time is required to be used in computing the total load to a feeder.

Largest

If installed by the electric utility, the conductors installed between pad mounted transformers and the meter

Lateral service conductors

The connection between the grounded circuit conductor and the equipment grounding conductor at the service

Main Bonding Jumper

Not higher than 6 ft 7 inches for panel boards

Mounting height

conductors between the Service Point and the first point of connection to the service- entrance conductors

Overhead service conductors

conductor installed between the pad-mounted transformer and the meter

Service Lateral Conductors

the overhead conductors between the utility distribution system and the service point

Service drop

The 3 VA per square foot general lighting load for dwelling units includes general use receptacles and lighting outlets.

True

Table 220.56 may be applied to determine the load for thermostatically controlled or intermittently used _____ and other kitchen equipment in a commercial kitchen.

all

The 3 VA per square foot general lighting load for dwelling units does not include _____.

all

To determine the feeder calculated load for ten 3 kW household cooking appliances, use _____ of Table 220.55.

col a

A device comprised of _____ or more receptacles shall be calculated at not less than 90 VA per receptacle.

four

When calculating a feeder or service load for existing installations, if the maximum demand data for a 1 year period is not available, the calculated load shall be permitted to be based on the maximum demand (the _____ kilowatts reached and maintained for a 15 minute interval) continuously recorded over a minimum 30 day period using a recording ammeter or power meter connected to the highest loaded phase of the feeder or service, based on the initial loading at the start of the recording.

highest average

Watts X hours/1000

kWh

When applying the demand factors of Table 220.56, the feeder or service demand load shall not be less than the sum of the _____.

largest two equipment loads


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