431

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a. nonlinear

No reduction in the size of the neutral conductor is permitted for ___-type lighting loads where supplied from a 4-wire, wye-connected, 3-phase system. Select one: a. nonlinear b. dwelling-unit c. hospital d. motel

b. are

Service-entrance or feeder conductors whose demand load is determined by the optional calculation ___ permitted to have the neutral load determined by 220.61. Select one: a. are not b. are

a. largest

Where it is unlikely that two or more loads will be in use simultaneously, it shall be permissible to assume that only the ___ load(s) will be on at any given time when computing the total load to a feeder. Select one: a. largest b. difference between the two c. smallest d. none of these

a. 180

Before demand factors are taken into consideration in commercial buildings, general-use receptacle loads are to be computed at not less than ___ VA per outlet. Select one: a. 180 b. 100 c. 150 d. 120

a. 410

A 500-ampere load supplied by a 120/240-V feeder requires a feeder neutral with an ampacity of ___ amps. Select one: a. 410 b. 280 c. 340 d. 350

a. for three hours or more

A continuous load is one expected to operate ___. Select one: a. for three hours or more b. without stopping c. at peak connected load d. none of these

d. 43

A demand factor of ___ percent applies to a multifamily dwelling with ten units, when the optional calculation method is used. Select one: a. 50 b. 60 c. 75 d. 43

c. 125 percent of the motor full-load current

Branch-circuit conductors supplying a single motor shall have an ampacity not less than ___ rating. Select one: a. 125 percent of the motor locked rotor current b. 125 percent of the maximum motor nameplate c. 125 percent of the motor full-load current d. 80 percent of the motor full-load current

b. I, II & IV only

For a dwelling unit, the computed floor area shall not include ___. I. carports II. garages III. bathrooms IV. open porches Select one: a. II & IV only b. I, II & IV only c. I, III & IV only d. I, II, III & IV

d. 300

For permanently connected appliances rated over ___ volt-amperes or 1/ 8-horsepower, the branch-circuit switch or circuit breaker shall be permitted to serve as the disconnecting means where it is located within sight of the appliance or is capable of being locked in the open position. Select one: a. 500 b. 400 c. 200 d. 300

d. 50

For warehouses, after the first 12.5 kVA, the remainder of the lighting load demand is calculated at _____ percent. Select one: a. 30 b. 20 c. 100 d. 50

b. 7

Given: You are installing 90 feet of multioutlet assembly in the computer lab of a school. The computers are likely to be used simultaneously. The minimum number of 20-amp, 120-volt, single-phase circuits required to feed the multioutlet assembly is ___. Select one: a. 4 b. 7 c. 5 d. 6

c. 100

If a protective device rating is marked on an appliance, the branch-circuit overcurrent protection device rating shall not be greater than ___ percent of the protective device rating marked on the appliance. Select one: a. 115 b. 80 c. 100 d. 50

a. 65.3 kVA

If an apartment complex has a lighting load of 205.4 kVA, what is the demand factor of this lighting load in kVA? Each apartment contains an electric range. (The optional method is not to be used.) Select one: a. 65.3 kVA b. 63.0 kVA c. 16.5 kVA d. 602 kVA

d. the calculated load after demand factors have been applied

The NEC® requires the ampacity of a feeder shall be equal to, or greater than ___. Select one: a. the connected load b. 125% of the overcurrent protection device c. the sum of all branch circuit overcurrent protection devices d. the calculated load after demand factors have been applied

d. nameplate

The connected load to which the demand factors of Table 220.84 apply include the ___ ratings of all appliances that are fastened in place, permanently connected, or located to be on a specific circuit. Select one: a. overcurrent protection b. calculated c. circuit d. nameplate

b. shall not

The demand factors of Table 220.42 ___ apply to the computed load of feeders to areas in hospitals, hotels, and motels where the entire lighting is likely to be used one at a time, as in operating rooms, ballrooms, or dining rooms. Select one: a. shall b. shall not

b. 5 kW

Using the general method of calculation, what is the minimum demand for a household clothes dryer? Select one: a. 6 kW b. 5 kW c. 4 kW d. 4.5 kW

c. 15,000

What is the demand load for eighty receptacles located in a 15,000-square-foot office building? Select one: a. 180 b. 14,400 c. 15,000 d. 12,200

d. 75

When calculating the service-entrance conductors for a farm service, the second-largest load of the total load, shall be computed at ___%. Select one: a. 90 b. 65 c. 80 d. 75

a. 0

When calculating the total load on a dwelling, how many VA per sq. ft. must be included for the general-use receptacles? Select one: a. 0 b. 1 c. 3 d. 2

a. 3000 VA

When calculating the total load on a dwelling, what is the minimum VA that must be added for the two required small-appliance circuits? Select one: a. 3000 VA b. 1200 VA c. 1500 VA d. 2400 VA

d. 40%

When using the optional calculation method for a dwelling unit service, all "other loads" above the initial 10 kW are to be listed at ___. Select one: a. 60% b. 75% c. 50% d. 40%

d. 5

Where fixed multioutlet assemblies are employed, each ___ feet or fraction thereof of each separate and continuous length shall be considered as one outlet of not less than 180 volt-amperes where the connected appliances are unlikely to be used simultaneously. Select one: a. 1 b. 10 c. 8 d. 5 e. 6

c. omit the smaller

Where it is unlikely that two dissimilar loads will be in use simultaneously, it shall be permissible to ___ of the two in computing the total load of a feeder. Select one: a. omit the larger b. omit neither c. omit the smaller d. omit both

b. 12.2 kW

A single-family dwelling unit has three ovens rated at 6, 8, and 3.5 kW; a cooktop rated at 6 kW, and a broiler rated at 3.5 kW. The minimum demand factor to be calculated for the ungrounded service entrance conductors is ___. Select one: a. 18.6 kW b. 12.2 kW c. 30.1 kW d. 27.3 kW

b. 1/ 4

A unit load of not less than ___ volt-amperes per square foot shall be included for storage spaces in other than dwellings. Select one: a. 3 b. 1/ 4 c. 1 d. 1/ 2

a. II & III only

For dwelling units, the computed floor area at 3 VA per square foot does NOT include ___. I. bathrooms II. garages III. open porches Select one: a. II & III only b. I, II & III c. I & III only d. I & II only

d. two

For each farm building or load supplied by ___ or more branch circuits, the load for feeders, service conductors, and service equipment shall be computed in accordance with the demand factors of Table 220.102. Select one: a. four b. one c. three d. two

a. 3.5

In a dwelling, the minimum feeder neutral for a 5 kVA clothes washer/dryer would be ___ kVA. Select one: a. 3.5 b. 5 c. 3.0 d. 4.3

c. I & II only

It shall be permissible to apply a demand factor of 75% to the nameplate rating load of 4 or more ___ fastened in place in a dwelling. I. water heaters II. dishwashers III. clothes dryers Select one: a. I only b. II only c. I & II only d. I, II & III

c. 8000

The minimum feeder load for a 40 foot long show window is ___ VA. Select one: a. 4000 b. 10,000 c. 8000 d. none of these

a. 20

The minimum number of 15-amp, 120-volt, lighting circuits required for a 12,000 sq. ft. multifamily dwelling is ___. Select one: a. 20 b. 15 c. 30 d. 24

c. 91

The minimum number of 20-amp, 277-volt, lighting circuits required for a 150,000 ft2 department store is ___. The actual connected lighting load is 400 kVA. Assume breakers are not rated for continuous use. Select one: a. 72 b. 102 c. 91 d. 82

c. 0.50

When a calculation results in a fraction of an ampere of ___ or more, the NEC® permits "rounding up" to the next ampere. Select one: a. 0.49 b. 0.51 c. 0.50 d. none of these

b. 200 VA per linear ft.

When calculating the load for show window lighting, ___ shall be included for this load. Select one: a. 120 VA per outlet b. 200 VA per linear ft. c. 180 VA per linear ft. d. 280 VA per outlet

d. 70

Where permissible, the demand factor applied to that portion of the unbalanced neutral feeder load in excess of 200 amps is ___ percent. Select one: a. 80 b. 125 c. 40 d. 70

c. The optional method of calculation is permitted if the service-entrance conductors have an ampacity of 200 or greater.

Which of the following is not true concerning the optional method for a dwelling unit? Select one: a. The neutral would be determined by section 220.61. b. A demand of 100% of the heat pump. c. The optional method of calculation is permitted if the service-entrance conductors have an ampacity of 200 or greater. d. A demand of 40% of the nameplate rating(s) of electric space heating of four or more separately controlled units can be applied.

Determine the maximum number of 120-volt, general-purpose receptacles the NEC® permits to be placed on a 20-amp, 120-volt, single-pole breaker in a commercial building. Select one: a. 15 b. 10 c. 13 d. 18

c. 13

b. 100

Fixed electric space heating loads shall be computed at ___ percent of the total connected load; however in no case shall a feeder load current be less than the rating of the largest branch circuit supplied. Select one: a. 115 b. 100 c. 125 d. 80

b. I, III & IV only

For a dwelling load calculation, the Code requires the inclusion of a minimum of ___. I. 3 volt-amps per square foot II. one 8 kW range III. two small-appliance circuits IV. one laundry circuit Select one: a. I, II & III only b. I, III & IV only c. I, II, III & IV d. I & II only

a. 70%

For a feeder supplying household cooking equipment and electric clothes dryers, the maximum unbalanced load on the neutral conductor shall be considered as ___ of the load on the ungrounded conductors. Select one: a. 70% b. 50% c. 80% d. 40%

c. 2

For other than dwelling units, the feeder and service-load calculation for track lighting is determined at 150 volt-amperes for every ___ feet of track installed. Select one: a. 6 b. 4 c. 2 d. none of these

a. 1500

In each dwelling unit, each small-appliance branch circuit shall be computed at not less than ___ volt-amperes. Select one: a. 1500 b. 180 c. 2 d. 3000

c. 75

It shall be permissible to apply a demand factor of ___% to the nameplate ratings of 4 or more fastened-in-place water heaters in a multifamily dwelling. Select one: a. 50 b. 80 c. 75 d. 90

b. 18,500 VA

What is the minimum demand load for general-purpose receptacles in an office building that has 150 receptacles? Select one: a. 27,000 VA b. 18,500 VA c. 13,500 VA d. 10,000 VA

b. 3/0 AWG

What size copper grounding electrode conductor is required for a service with three sets of 500 kcmil copper per phase? Select one: a. 1 AWG b. 3/0 AWG c. 2/0 AWG d. 1/0 AWG

b. 4

The minimum number of 120-volt, 15-amp lighting branch circuits required for a dwelling that has 70 × 30 ft. of livable space is ___. Select one: a. 5 b. 4 c. 3 d. 2

a. 500

A previously unwired portion of an existing residence or a structural addition to an existing residence, either of which exceeds ___ square feet, shall be computed in accordance with sections 220.12 and 220.14. Select one: a. 500 b. 250 c. 300 d. 100

b. 90 VA

A single piece of equipment consisting of a multiple receptacle comprised of four or more receptacles shall be computed at not less than ___ per receptacle. Select one: a. 180 VA b. 90 VA c. 15 A d. 20 A e. 200 VA

c. outside

When determining the load on the "volt-amps per square foot" basis, the floor area shall be computed from the ___ dimensions of the building. Select one: a. midpoint b. inside c. outside d. any of these

c. 100

For a dwelling unit served by a single set of 3-wire, 120/240-volt or 208Y/120-volt service-entrance conductors with an ampacity of ___ or greater, it is permissible to compute the feeder and service loads in accordance with 220.82(B) and (C) instead of the method specified in Part III of Article 220. Select one: a. 125 b. 175 c. 100 d. 150

c. both I and II

The optional method of calculation is permitted for a multifamily dwelling if ___. I. each dwelling unit is equipped with either electric space heating or air conditioning or both II. no dwelling unit is supplied by more than one feeder Select one: a. I only b. II only c. both I and II d. neither I nor II

a. 12.5

When service-entrance conductors exceed 1100 kcmil for copper, the required grounded conductor must be sized not less than ___ percent of the area of the largest phase conductor. Select one: a. 12.5 b. 25 c. 15 d. 19


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