Journeyman Electrician (NEC) — All Questions

In box-fill calculations, how is a device yoke or strap counted?

• a.As two conductor volume allowances, based on the largest conductor connected to the device✓
• b.It is not counted at all
• c.As one conductor volume allowance
• d.As two allowances, based on the smallest conductor

Each yoke or strap containing a device or utilization equipment is counted as two conductor volume allowances based on the largest conductor connected to it. See NEC 314.16(B)(4).

In a dwelling-unit load calculation, how are the general-use 15- and 20-ampere receptacle outlets handled?

• a.They are calculated at 180 volt-amperes each in addition to the lighting load
• b.They are omitted from the load calculation entirely
• c.They are calculated at 1.5 amperes each
• d.They are included in the general lighting volt-amperes and are not calculated separately✓

In dwelling units, general-use receptacle outlets and lighting outlets are considered part of the general lighting load at 3 VA per square foot and no additional volt-amperes are added for them. See NEC 220.14(J).

An equipment grounding conductor of the wire type is never required to be larger than what?

• a.The circuit conductors supplying the equipment✓
• b.Twice the value shown in Table 250.122
• c.6 AWG copper in all cases
• d.The ungrounded service conductor size in every case

An equipment grounding conductor need not be larger than the circuit conductors supplying the equipment. See NEC 250.122(A).

A branch circuit supplies a 32-ampere continuous load. Using 75 degrees C copper terminations, what is the minimum conductor size?

• a.6 AWG
• b.10 AWG
• c.12 AWG
• d.8 AWG✓

The conductor must carry at least 125 percent of the continuous load: 32 x 1.25 = 40 A. In the 75 degrees C column 10 AWG (35 A) fails and 8 AWG (50 A) qualifies. See NEC 210.19(A) and Table 310.16.

What is the rule for a bare aluminum grounding electrode conductor near the earth?

• a.It must be installed within 18 inches of the earth
• b.It may not be used in direct contact with earth or masonry, or within 18 inches of the earth✓
• c.It may be buried directly in the earth like copper
• d.Aluminum grounding electrode conductors are prohibited entirely

Bare or exposed aluminum grounding electrode conductors may not be used in direct contact with masonry or earth or where subject to corrosive conditions, and may not be terminated within 18 inches of the earth. See NEC 250.64(A).

Which dwelling-unit location requires arc-fault circuit-interrupter protection for 120-volt, 15- and 20-ampere branch circuits?

• a.A bathroom
• b.A bedroom✓
• c.An unfinished basement
• d.An outdoor receptacle

AFCI protection covers most habitable dwelling areas, including bedrooms, kitchens, living rooms and laundry areas. Bathrooms, unfinished basements and outdoor receptacles are addressed by GFCI rather than AFCI requirements. See NEC 210.12(A).

How must the multiple grounding electrodes present at a building be arranged?

• a.Electrodes must be at least 100 feet apart
• b.A ground rod may never be combined with a water pipe electrode
• c.All electrodes present must be bonded together to form the grounding electrode system✓
• d.Only one electrode is permitted per building

All grounding electrodes that are present, such as a water pipe, concrete-encased electrode and ground rods, must be bonded together to form the grounding electrode system. See NEC 250.50.

Which dwelling-unit location requires GFCI protection for 125-volt, 15- and 20-ampere receptacles?

• a.A living-room wall receptacle
• b.A bedroom receptacle
• c.A hallway receptacle
• d.A garage✓

NEC 210.8(A) lists garages among the GFCI areas along with bathrooms, kitchens, laundry areas, basements, crawl spaces and outdoors. Living rooms, bedrooms and hallways are AFCI areas instead.

A feeder supplies a 60-ampere continuous load. What is the minimum standard overcurrent device rating?

• a.70 amperes
• b.75 amperes
• c.80 amperes✓
• d.90 amperes

60 x 1.25 = 75 A, which is not a standard rating, so the next standard size of 80 A must be used. See NEC 215.3 and 240.6(A).

An electric-vehicle supply equipment branch circuit serves a 40-ampere EV charging load. What minimum overcurrent device and conductor ampacity are required?

• a.50 amperes✓
• b.45 amperes
• c.60 amperes
• d.40 amperes

Electric-vehicle charging load is treated as continuous, so the overcurrent device and conductors are sized at 125 percent: 40 x 1.25 = 50 A. See NEC 625.41 and 625.42.

A dwelling has a combined general lighting, small-appliance and laundry load of 3,600 volt-amperes. Applying the standard demand factors, what is the demand load?

• a.3,600 volt-amperes
• b.3,150 volt-amperes
• c.3,210 volt-amperes✓
• d.1,260 volt-amperes

The first 3,000 VA is taken at 100 percent and the remainder at 35 percent: 3,000 + (600 x 0.35) = 3,210 VA. See NEC Table 220.45.