Free Electrician Practice Test (20 Questions) | ExamsLib

Question 1

Which conductor connects the grounded circuit conductor (neutral) to the grounding electrode at the service?

Accepted Answer

Main bonding jumper

Answer

Equipment grounding conductor

Answer

Grounding electrode conductor

Answer

System bonding jumper

Question 2

In a residential installation, the equipment grounding conductor (EGC) in a branch circuit is normally identified by which color or marking?

Accepted Answer

Green, green with yellow stripes, or bare

Answer

White or gray

Answer

Black or red

Answer

Orange or brown

Question 3

What NEC concept governs the maximum number of overcurrent devices permitted in a panelboard?

Accepted Answer

A panelboard is limited to 42 overcurrent devices (poles), not counting the main breaker, per NEC rules

Answer

A panelboard may contain an unlimited number of overcurrent devices as long as the bus rating is not exceeded

Answer

The number is limited only by the physical space available in the enclosure

Answer

A panelboard may contain no more than 20 overcurrent devices regardless of size

Question 4

A 240V, single-phase motor has a full-load current (FLC) of 18A. Using NEC Table 430.52, what is the maximum rating of an inverse-time circuit breaker permitted as the branch-circuit short-circuit and ground-fault protective device?

Accepted Answer

45A

Answer

25A

Answer

40A

Answer

50A

Question 5

A metal water pipe enters a building and is used as a grounding electrode. The pipe must be supplemented with an additional electrode when a water meter or other isolating fitting is located within what distance of the point of entry into the building?

Accepted Answer

5 ft

Answer

3 ft

Answer

10 ft

Answer

25 ft

Question 6

Six 12 AWG THHN current-carrying conductors are run in a single EMT conduit at an ambient temperature of 40 degrees C. Using NEC Table 310.16 (90 degrees C column base ampacity of 30 A), the 40 degrees C temperature correction factor of 0.91, and the 6-conductor adjustment factor of 0.70, what is the corrected ampacity?

Accepted Answer

19.1 A

Answer

21.0 A

Answer

27.3 A

Answer

16.4 A

Question 7

Which of the following best describes the purpose of a ground rod as a grounding electrode?

Accepted Answer

It dissipates static charges, lightning surges, and establishes earth reference voltage for the system

Answer

It provides the primary fault-current return path during a ground fault

Answer

It limits the current on the neutral conductor

Answer

It replaces the need for an equipment grounding conductor in branch circuits

Question 8

An equipment grounding conductor (EGC) must be sized based on which of the following?

Accepted Answer

The rating of the overcurrent protective device (OCPD) protecting the circuit

Answer

The ampacity of the phase conductors it runs with

Answer

The length of the circuit run

Answer

The total load served by the circuit in amperes

Question 9

A residential dwelling has 2,000 sq ft of living space. Using 3 VA/sq ft for general lighting and applying 100% demand on the first 3,000 VA and 35% on the remainder, what is the calculated general lighting demand load?

Accepted Answer

4,050 VA

Answer

6,000 VA

Answer

2,100 VA

Answer

3,000 VA

Question 10

An electrician is installing a sign on a commercial building exterior. According to NEC principles, what is the minimum ampere rating for the dedicated branch circuit supplying an exterior sign outlet?

Accepted Answer

20 A

Answer

15 A

Answer

30 A

Answer

50 A

Free Electrician Practice Test

Question 1

Which conductor connects the grounded circuit conductor (neutral) to the grounding electrode at the service?

Question 2

In a residential installation, the equipment grounding conductor (EGC) in a branch circuit is normally identified by which color or marking?

Question 3

What NEC concept governs the maximum number of overcurrent devices permitted in a panelboard?

Question 4

A 240V, single-phase motor has a full-load current (FLC) of 18A. Using NEC Table 430.52, what is the maximum rating of an inverse-time circuit breaker permitted as the branch-circuit short-circuit and ground-fault protective device?

Question 5

A metal water pipe enters a building and is used as a grounding electrode. The pipe must be supplemented with an additional electrode when a water meter or other isolating fitting is located within what distance of the point of entry into the building?

Question 6

Question 7

Which of the following best describes the purpose of a ground rod as a grounding electrode?

Question 8

An equipment grounding conductor (EGC) must be sized based on which of the following?

Question 9

A residential dwelling has 2,000 sq ft of living space. Using 3 VA/sq ft for general lighting and applying 100% demand on the first 3,000 VA and 35% on the remainder, what is the calculated general lighting demand load?

Question 10

An electrician is installing a sign on a commercial building exterior. According to NEC principles, what is the minimum ampere rating for the dedicated branch circuit supplying an exterior sign outlet?

Question 11

Structural steel that is grounded and interconnected to form a metal building frame may serve as a grounding electrode. What minimum length of steel must be in direct contact with the earth to qualify under NEC 250.52(A)(2)?

Question 12

What is the function of the grounding electrode conductor (GEC)?

Question 13

What is the color marking required by the NEC for a grounded conductor (neutral) of sizes 6 AWG and smaller?

Question 14

When calculating the general lighting load for a dwelling using the NEC standard method, what unit load (VA per square foot) is applied to the gross floor area?

Question 15

A dwelling unit has a gross floor area of 1,800 sq ft. Using the NEC standard method, what is the general lighting load in VA before any demand factors are applied?

Question 16

A feeder supplies four electric ranges with nameplate ratings of 12 kW each. Using NEC Table 220.55, what is the maximum demand load (in kW) for these four ranges?

Question 17

A 240-volt, single-phase household electric range is rated at 12 kW. Using NEC Table 220.55 Column C (one range), what demand load is used for service calculations?

Question 18

What does 'demand factor' mean in load calculations?

Question 19

What is the purpose of adding two small appliance branch circuit loads (each at 1,500 VA) to a residential load calculation?

Question 20

What is the purpose of the National Electrical Code (NEC)?