Residential Electrician Exam #3

The MINIMUM size copper equipment grounding conductor required to equipment served by a 40-ampere rated branch-circuit is _____. a) 10 AWG b) 8 AWG c) 12 AWG d) 14 AWG

A: 10 AWG Ref: Tbl. 250.122

What is the MAXIMUM allowable voltage between conductors on a branch-circuit supplying luminaires in a residence? a) 120 volts b) 150 volts c) 240 volts d) 250 volts

A: 120 volts Ref: 210.6(A)(1)

When calculating the total load on a dwelling unit, how many VA per square feet must be included for the general purpose receptacle outlets? a) none b) one c) two d) three

A: none Ref: 220.14(J)(1)

What is the MINIMUM size copper SE cable with type THHW insulation that may be used as ungrounded, service-entrance phase conductors for a 150 ampere-rated, 120/240-volt, singlephase, residential service? a) 1/0 AWG b) 1 AWG c) 2 AWG d) 3 AWG

B: 1 AWG Ref: Tbl. 310.15(B)(6)

The NEC requires recessed portions of luminaire enclosures that are not identified for contact with insulation, to be spaced from combustible material a MINIMUM of _____. a) 3⁄8 inch b) 1⁄2 inch c) 3⁄4 inch d) 1 inch

B: 1/2 inch Ref: 410.116(A)(1)

What is the MAXIMUM allowable standard size circuit breaker rating that may be used to protect a size 8 AWG copper NM-B cable supplying an electric range? a) 30 amperes b) 40 amperes c) 50 amperes d) 60 amperes

B: 40 amperes Ref: 334.80; Tbl. 310.16

A 240-volt, single-phase, 30-ampere rated, electric clothes dryer has a VA rating of _____. a) 5,000 VA b) 7,200 VA c) 8,000 VA d) 15,400 VA

B: 7,200 VA Sol: P = I x E P = 30 amperes x 240 volts = 7,200 VA

It shall be permissible to apply a demand factor of _____ percent to the nameplate-rating load of four or more fastened in place electric water heaters in a multi-family dwelling unit. a) 50 b) 75 c) 80 d) 90

B: 75 Ref: 220.53

A connection to a driven or buried grounding electrode shall ______. a) be accessible b) not be required to be accessible c) not permitted to be buried d) be visible

B: not be required to be accessible Ref: 250.68(A), Ex.1

When two single-pole switches are mounted on the same strap, the number of conductors permitted in the box shall be reduced by _____ conductor(s). a) one b) two c) three d) four

B: two Ref: 314.16(B)(4)

When installing NM cable through bored holes in wooden studs, the holes shall be bored so that the edge of the hole is not less than _____ from the edge, or the cable shall be protected by a steel plate at least 1⁄16 inch thick. a) 3⁄4 inch b) 1 inch c) 1 1⁄4 inches d) 1 1⁄2 inches

C: 1 1/4 inches Ref: 300.4(D)

The rating of any single cord-and-plug connected appliance supplied by a 30-ampere rated branch-circuit shall not exceed _____. a) 30 amperes b) 27 amperes c) 24 amperes d) 16 amperes

C: 24 amperes Ref: 210.23(B) Sol: 30 amperes x 80 percent = 24 amperes

For outlet boxes designed to support ceiling-suspended (paddle) fans that weigh more than _____ pounds, the required marking shall include the maximum weight to be supported. a) 20 b) 30 c) 35 d) 70

C: 35 Ref: 314.27(D)

When doing residential service and feeder calculations, electric clothes dryers are to be calculated at a MINIMUM of _____ watts (VA) or the nameplate rating, whichever is larger. a) 3,000 b) 4,500 c) 5,000 d) 6,000

C: 5,000 Ref: 220.54

Determine the MINIMUM number of 15-ampere, 120-volt general lighting branch-circuits required for a dwelling that has 2,600 square feet of habitable space. a) three b) four c) five d) six

C: five Ref: 220.12; Tbl. 220.12 Sol: 2,600 sq. ft. x 3 VA = 7,800 VA (total lighting VA of house) 120 volts x 15 amperes = 1,800 VA (one circuit) 7,800 VA (house)/1,800 VA (one circuit) = 4.3 = 5 circuits

The MAXIMUM number of size 10 AWG conductors permitted in a 4 inch x 11⁄4 inch octagon metal junction box is _____. a) two b) four c) five d) six

C: five Ref: Tbl. 314.16(A)

Switches and circuit breakers used as a disconnecting means to appliances shall be _____. a) factory installed only b) of the fusible type c) of the indicating type d) of the tripping type

C: of the indicating type Ref: 422.35

When installing luminaires without GFCI protection above an indoor spa or hot tub, they are required to be mounted at LEAST _____ above the maximum water level of the spa or hot tub. a) 5 feet b) 7 feet, 6 inches c) 6 feet, 7 inches d) 12 feet

D: 12 feet Ref: 680.43(B)(1)(a)

The ampacity of the branch-circuit conductors to a residential central heating electric furnace shall NOT be less than _____ percent of the furnace load. a) 80 b) 100 c) 115 d) 125

D: 125 Ref: 424.3(B); 210.19(A)(1)

When calculating the total load for a dwelling unit, what is the MINIMUM load, in VA, that must be added for the two required small appliance branch-circuits? a) 1,200 VA b) 1,500 VA c) 2,400 VA d) 3,000 VA

D: 3,000 VA Ref: 220.52(A) Sol: 1,500VA x 2 circuits required = 3,000VA

In dwelling units, at least one wall receptacle shall be installed in bathrooms; the receptacle outlet shall be within at LEAST _____ of the outside edge of each basin. a) 12 inches b) 18 inches c) 24 inches d) 36 inches

D: 36 inches Ref: 210.52(D)

What is the MAXIMUM allowable cord length for the cord supplying a cord-and-plug connected dishwasher installed under a kitchen counter in a dwelling unit? a) 11⁄2 feet b) 2 feet c) 3 feet d) 4 feet

D: 4 feet Ref: 422.16(B)(2)(2)

A branch-circuit supplying a 5 kW wall-mounted oven and a 7 kW counter-mounted cooktop in a residence will have a demand load of _____ on the ungrounded service-entrance conductors when applying the general (standard) method of calculation for dwellings. a) 12 kW b) 9.5 kW c) 8.0 kW d) 7.8 kW

D: 7.8 kW Ref: Tbl. 220.55 and Note 3 Sol: Use column B-2 appliances 65% demand 5 KW + 7 KW = 12 KW (total connected load) 12 KW x 65 percent = 7.8 KW (demand load)

In general, all receptacles installed on 15- and 20-ampere, 120- volt branch-circuits are required to _____. a) be GFCI protected b) have a nonmetallic faceplate c) be of the ungrounded type d) be of the grounding type

D: be of the grounding type Ref: 406.3(A)

Type XHHW insulated conductors are permitted to be used in _____. a) dry locations only b) wet locations only c) dry or damp locations only d) dry, damp, or wet locations

D: dry, damp, or wet locations Ref: Tbl. 310.13(A); 310.8(B) and (C)(2)