art 220

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A minimum of _____ 20A small-appliance branch circuit(s) is(are) required for receptacle outlets in the kitchen, dining room, breakfast room, pantry, and similar areas.

two

The NEC recognizes that the general lighting and general-use receptacles, and the small-appliance and laundry circuits won't all be on or loaded at the same time and permits a(an) ______ to be applied to the total of these loads.

demand factor

A demand load factor of 75 percent is permitted for _____ or more fixed appliances such as disposals (waste), dishwashers, trash compactors, water heaters, motors, and so forth.

four

The service neutral load for household electric clothes dryers is permitted to be calculated at _____ percent of the load as determined by 220.54.

70

How many 20A, 120V lighting circuits are required for a 1,900 sq ft dwelling unit?

3 circuits

Using the optional method, calculate the service load in amperes for a 2,350 sq ft single-family dwelling containing the following loads: dishwasher 11A at 120V, disposal (waste) 6A at 120V, water heater 4,500 W at 240V, dryer 4.50 kW at 240V, range 9.10 kW at 240V, air-conditioning 20A at 240V, and five heat strips 2 kW at 240V.

98A

When sizing the feeder or service conductor according to the optional method we must:

Determine the total connected load of the general lighting and general-use receptacles, small-appliance and laundry branch circuits, and the nameplate VA rating of all fixed appliances and motors. Determine the demand load by applying the following demand factors to the total connected load: the first 10 kVA at 100 percent, and the remainder at 40 percent. Determine the larger of air-conditioning versus heat demand load.

How many 15A or 20A, 120V circuits are required for the general lighting and general-use receptacles for a dwelling having a floor area of 2,400 sq ft, exclusive of an unfinished basement not adaptable for future use?

Three 20A or four 15A circuits

Because the air-conditioning and space electric heating loads aren't on at the same time they're called \"noncoincidental,\" and it's permissible to omit the smaller of the two loads.

True

The NEC doesn't require a separate circuit for the washing machine but does require a separate circuit for the laundry room receptacle or receptacles, of which one can be for the washing machine.

True

The feeder or service neutral load is the maximum unbalanced calculated load between the neutral conductor and any one phase conductor as determined by Article 220. Since 240V loads can't be connected to the neutral conductor, 240V loads aren't considered for sizing the feeder grounded conductor.

True

Where there are no adjustment or correction factors required, the service conductors for a rated service of _____ supplying the entire load associated with an individual dwelling unit, may be sized applying Table 310.12.

all of these

What size service conductors are required if the demand load for a dwelling unit equals 140A, the service disconnect is rated 150A?

1 AWG

Using the optional method, what size 120/240V single-phase aluminum service conductor is required for a 1,500 sq ft dwelling unit containing the following loads? Disposal (Waste), 1 kVA Dishwasher, 1.50 kVA Water Heater, 5 kW Dryer, 5.50 kW Cooktop, 6 kW Two Ovens, each 3 kW Two separately controlled 5 kW space-electric heating units Air-Conditioning, 17A, 240V

1 AWG AL

Using the optional method, what size 120/240V single-phase aluminum service conductor is required for a 1,500 sq ft dwelling unit containing the following loads?Disposal (Waste), 1 kVADishwasher, 1.50 kVAWater Heater, 5 kWDryer, 5.50 kWCooktop, 6 kWTwo Ovens, each 3 kWTwo separately controlled 5 kW space-electric heating units Air-Conditioning, 17A, 240V

1 AWG AL

Using the optional method, what size 120/240V single-phase aluminum service conductor is required for a 2,000 sq ft dwelling unit to which air-conditioning of 16A at 240V and 8 kW heat is to be added? It contains the following existing loads.Dishwasher, 1,500 VADisposal (Waste), 1,000 VAWater Heater, 4,500 WDryer, 5,500 WRange, 12,000 W

1/0 AWG AL

What's the calculated feeder demand load for one 12 kW range and one 6 kW cooktop?

11 kW

Using the standard method, calculate the service load for a 950 sq ft single-family dwelling containing the following loads: range 8 kW at 240V, dryer 4.50 kW at 240V, dishwasher 12A at 120V, water heater 4,000W at 240V, air conditioner 28A at 240V, and electric heat 9,600W at 240V.

129A

Using the standard method, calculate the service demand load in amperes for a 2,200 sq ft single-family dwelling containing the following loads: range 14.40 kW at 240, dryer 4.80 kW at 240V, dishwasher 1.20 kVA at 120V, disposal (waste) 9.80A at 120V, microwave 1.92 kVA at 120V, water heater 4.20 kW, two air-conditioning units 12A at 120V, and electric heat 6 kW at 240V.

133A

What's the service demand load for two 6 kW ovens, one 3.50 kW cooktop, and three 8 kW ranges?

17 kW

What's the branch-circuit load for a 3 kW oven in a dwelling unit?

3 kW

An apartment building contains 20 units, each is 840 sq ft. What's the general lighting and general-use receptacle feeder demand load for each dwelling unit? Note: Laundry facilities are provided in a common area; a laundry circuit isn't required in each unit [210.52(F) Ex 1].

3,882 VA

What size service conductors paralleled in two raceways are required for the following dwelling unit demand loads of 136,956 VA? The system is 120/240V, single-phase.

300 kcmil copper or 500 kcmil aluminum

Using the optional load calculations, what's the air-conditioning versus heat load for an air conditioner/heat pump (20A at 240V) for a dwelling unit?

4,800 VA

A dwelling unit has one 6 kW cooktop and one 6 kW oven. What's the minimum feeder demand load for the cooking appliances?

7.80 kW

What's the feeder neutral load for one 6 kW household dryer?

4.20 kW

What's the feeder or service demand load for a 4 kW dryer?

5 kW

What's the demand load for the general lighting, small-appliance, and laundry circuits for a 1,500 sq ft dwelling unit?

5,100 VA

What's the service demand load for an air conditioner (18A, 240V) and electric heating (4 kW)?

5,400 VA

A dwelling unit contains one of each of the following: dishwasher (9.80A at 120V) and water heater (4 kW). What's the fixed appliance demand load for the dwelling unit?

5.20 kVA

What's the service demand load for a dwelling unit with one dishwasher (1.50 kVA) and one water heater (4 kW)?

5.50 kVA

A dwelling unit contains a 5.50 kW electric clothes dryer. What's the feeder demand load for the dryer?

5.50 kW

What's the feeder or service demand load for a 5.50 kW dryer?

5.50 kW

What's the dwelling unit service neutral load for one 9 kW range?

5.60 kW

Using the standard method, calculate the service neutral load for a 950 sq ft single-family dwelling containing the following loads: range 8 kW at 240V, dryer 4.50 kW at 240V, dishwasher 12A at 120V, water heater 4 kW at 240V, air conditioner 28A at 240V, and electric heat 9.60 kW at 240V.

58A

How many 15A, 120V lighting circuits are required for a 3,400 sq ft dwelling unit?

6 circuits

What's the branch-circuit demand load for one 6 kW counter-mounted cooking unit in a dwelling unit?

6 kW

What's the feeder or service demand load for a disposal (waste) (940 VA), a dishwasher (1,250 VA), and a water heater (4,500 W)?

6,690 VA

Using the standard method, calculate the service load in amperes for a dwelling that has a floor area of 1,500 sq ft, exclusive of an unfinished basement not adaptable for future use, unfinished attic, and open porches. Cooking appliances are a 12 kW range and a 5.50 kW, 240V dryer.

78A

What's the feeder or service demand load for a dwelling unit (120/240V) containing an air conditioner motor-compressor rated 17A, 240V versus 8 kW of space electric heating? The air conditioner motor- compressor isn't the largest motor-type load in the dwelling unit.

8 kVA

What's the feeder or service demand load for a dwelling unit (120/240V) containing an air conditioner motor-compressor rated 18A at 240V versus 8 kW of space electric heating? The air conditioner motor- compressor is the largest motor-type load in the dwelling unit.

8 kVA

What's the branch-circuit demand load for a 12 kW range in a dwelling unit?

8 kW

What's the feeder or service demand load for a dwelling unit (120/240V) containing an air conditioner motor-compressor rated 23A at 240V versus 8 kW of space electric heating? The air conditioner motor- compressor isn't the largest motor-type load in the dwelling unit.

8 kW

What's the feeder or service demand load for a dwelling unit (120/240V) containing an air conditioner motor-compressor rated 28A, 240V versus 8 kW of space electric heating? The air conditioner motor- compressor is the largest motor-type load in the dwelling unit.

8.40 kVA

Using the optional method, calculate the service load for a 950 sq ft single-family dwelling containing the following loads: dishwasher 12A at 120V, disposal (waste) 6A at 120V, water heater 4,500 W at 240V, dryer 4.50 kW at 240V, range 8 kW at 240V, two air-conditioning units each 16A at 120V, and electric heat 5 kW at 240V.

100A

What's the feeder or service demand load for a dwelling unit containing a heat-pump motor-compressor of 17A at 240V with 6 kW of supplemental space electric heating 240V? The air conditioner motor- compressor is the largest motor-type load in the dwelling unit.

11.10 kVA

A 2,400 sq ft residence contains the following loads: One 1.50 kVA dishwasher, a 1 kVA disposal (waste), a 4.50 kW water heater, a 5.50 kW dryer, a 12 kW Range, a 24A, 240V air conditioner, and five 2 kW baseboard heaters. Using the optional method, the service size will be _____ for a 120/240V single-phase system.

110A

After all demand factors have been taken into consideration, the demand load for a single-family dwelling service is a 24,221 VA, 120/240V, single-phase system. The minimum service size is _____.

110A

Using the optional method, calculate the service load in amperes for a dwelling with a floor area of 1,500 sq ft, exclusive of an unfinished basement not adaptable for future use, unfinished attic, and open porches. It has two 20A small-appliance circuits, one 20A laundry circuit, two 4 kW wall-mounted ovens, one 5.10 kW counter-mounted cooking unit, a 4.50 kW water heater, a 1.20 kW dishwasher, a 5 kW combination clothes washer and dryer, six 7A, 240V room air-conditioning units, and a 1.50 kW permanently installed bathroom space heater.

122A

A 1,800 sq ft residence contains the following loads: One 1.50 kVA dishwasher, a 1 kVA disposal (waste), a pool motor (1.60 kVA), a 4 kW water heater, a 4.50 kW dryer, a 6 kW cooktop, two 3 kW ovens, a 28A, 240V air conditioner, and five 2 kW baseboard heaters. Using the optional method, the service size will be _____ for a 120/240V single-phase system with terminals rated 75°C.

125A

If the total demand load is 30 kVA for a 120/240V dwelling unit, what's the copper conductor size?

2 AWG

What size service conductors are required if the demand load for a dwelling unit equals 120A, the service disconnect is rated 125A?

2 AWG

What's the service demand load for the lighting, receptacles, small-appliance circuits, and laundry circuits for a 1,800 sq ft dwelling unit?

5,415 VA

What's the feeder or service demand load for a disposal (waste) (940 VA), a dishwasher (1,250 VA), a trash compactor (1,100 VA), and a water heater (4,500 W)?

5,843 VA

The feeder or service neutral load for household cooking appliances, such as electric ranges, wall- mounted ovens, or counter-mounted cooking units, is permitted to be calculated at _____ percent of the load as determined by 220.55.

70

What's the feeder or service demand load for a dwelling unit with a 17A, 240V air conditioner motor- compressor versus 8 kW of space electric heating 240V? The air conditioner motor-compressor isn't the largest motor-type load in the dwelling unit.

8 kW

What's the feeder or service demand load for a dwelling unit with a 28A, 240V air conditioner motor- compressor versus 8 kW of space electric heating at 240V? The air conditioner motor-compressor isn't the largest motor-type load in the dwelling unit.

8 kW

What's the branch-circuit demand load for a 13.60 kW range in a dwelling unit?

8.80 kW

What's the feeder or service demand load for a 13.60 kW range?

8.80 kW

What's the service demand load for a 14 kW range?

8.80 kW

Using the standard method, calculate the service neutral load in amperes for a 2,200 sq ft single-family dwelling containing the following loads: range 14.40 kW at 240V, dryer 4.80 kW at 240V, dishwasher 1.20 kVA at 120V, disposal (waste) 9.80A at 120V, microwave 1.92kVA at 120V, water heater 4.20 kW, two air-conditioning units 12A at 120V, and electric heat 6 kW at 240V.

83A

What's the feeder or service demand load for a dwelling unit containing a 28A, 230V air conditioner motor-compressor and three baseboard heaters (3 kW each)? The air conditioner motor-compressor is the largest motor-type load in the dwelling unit.

9,000 VA

What's the calculated demand load for a 16 kW oven in a dwelling unit?

9,600 W

Using the optional load calculations, what's the service demand load for an air conditioner/heat pump (20A at 240V) with 7.50 kW supplementary heat for a dwelling unit?

9,675 VA

The minimum feeder demand load for two 3 kW wall-mounted ovens and one 6 kW cooktop is _____.

9.30 kW

What's the feeder or service demand load for one 6 kW and two 3 kW cooking appliances?

9.30 kW

What's the calculated service load for one 3.50 kW cooktop, one 6 kw oven, and one 8 kW range?

9.63 kW

Household cooking appliances rated 1kW can have the feeder and service demand loads calculated according to the demand factors of Table 220.55.

False


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