Practice test

Free Electrician Practice Test

Take our free electrician practice test with 20 questions covering NEC code, grounding and bonding, and load calculations. See your score instantly.

These questions are for study practice only and are not official exam questions.

Question 1

1

What is the standard unit used to express electrical power in load calculations?

Question 2

2

What does AFCI protection do that standard circuit breakers do not?

Question 3

3

A concrete-encased electrode (Ufer ground) must consist of at least how many feet of bare copper wire or steel rebar encased in concrete near the bottom of a foundation footing?

Question 4

4

A 20A, 120V branch circuit supplies a single receptacle. What is the maximum continuous load that may be placed on this circuit per NEC requirements?

Question 5

5

The NEC informational notes recommend limiting voltage drop on a branch circuit to what maximum percentage for satisfactory equipment operation?

Question 6

6

A 208-volt, 3-phase induction motor has a nameplate full-load current (FLC) of 18 amperes. What is the minimum branch circuit conductor ampacity required by the NEC?

Question 7

7

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

Question 8

8

Under general NEC principles, which of the following is required for a circuit supplying a single motor?

Question 9

9

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

Question 10

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

11

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 12

12

Which conductor in a standard branch circuit is used to bond metal equipment enclosures back to the panel?

Question 13

13

For a continuous load, why must the overcurrent protective device (OCPD) and branch circuit conductors be rated at 125% of the load?

Question 14

14

A motor is rated 10 hp at 240 V, single-phase. Its full-load current (FLC) from the code table is 50 A. What is the minimum conductor ampacity required to supply this motor?

Question 15

15

What is the concept of 'box fill' and why is it important?

Question 16

16

Which NEC term describes the conductive connection that joins together metal parts of an electrical system to establish electrical continuity, but is NOT intended to carry fault current to earth?

Question 17

17

Two separate buildings on the same property are supplied from a common service. An equipment grounding conductor is run with the feeder to the second building. Which statement is correct regarding the neutral-to-ground bond at the second building's panelboard?

Question 18

18

When calculating the load for a commercial kitchen with multiple pieces of electric cooking equipment, which approach is commonly permitted to reduce the calculated load?

Question 19

19

In a standard residential load calculation, what demand factor is applied to a single electric clothes dryer in a single dwelling unit?

Question 20

20

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?

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