Previous NEC 2023 Code Questions Practice Test 9 Next NEC 2020 Code Questions Practice Test 12

NEC_PRACTICE NEC 2020

NEC 2020 Code Questions Practice Test 11

Free NEC 2020 practice test with 30 questions on working space, grounding electrodes, wiring methods, and overcurrent protection basics. Plain-English questions with full explanations.

TOPICS COVERED

NEC Practice Tests

How this test works

Read each question carefully

Look for absolute words like always / never — they often distinguish the right answer.

Manage your time

You have 45 min for 30 questions. Skip tough ones and come back.

Progress is auto-saved

Your answers are saved locally — a page refresh won't lose your work.

Review your answers

After submitting you'll see every explanation and your NEC references.

How to Use This Practice Test

This NEC 2020 Code Questions Practice Test 11 has 30 questions with detailed answers and NEC references. Take the full test, review every wrong answer, and look up the NEC article it references before moving on.

Tip: Mixed-format test — questions jump between topics just like the real exam. Don't spend more than 90 seconds on any one question.

Topics covered: All NEC chapters — branch circuits, grounding, conductors, wiring methods, motors, and more.
Passing score: Aim for 80%+ consistently before scheduling your exam.
Questions: 30 multiple-choice, one correct answer each

Questions

45 min

Time

70%

Pass

Timer starts immediately. Progress is auto-saved.

NEC 2020 Code Questions Practice Test 11 — Question List

Question 1: A panel is rated 120 volts to ground. Live parts are on one side only. What is the minimum working space depth in front of the panel?

2 feet
3 feet
4 feet
6 feet

NEC Reference: NEC 110.26(A)(1)

Question 2: What is the minimum width of the working space in front of electrical equipment?

24 inches
30 inches
36 inches
48 inches

NEC Reference: NEC 110.26(A)(2)

Question 3: What is the minimum headroom required for working space around electrical equipment rated 1000 volts or less?

5 feet
6 1/2 feet
7 1/2 feet
8 feet

NEC Reference: NEC 110.26(E)

Question 4: Working spaces about service equipment and panelboards must be provided with:

Illumination
Air conditioning
Carpet flooring
No special requirement

NEC Reference: NEC 110.26(D)

Question 5: Live parts of equipment operating at 50 volts or more must be:

Left open for easy access
Guarded against accidental contact
Painted red only
Removed from the building

NEC Reference: NEC 110.27(A)

Question 6: Per NEC Article 100, "in sight from" means visible and not more than what distance away?

25 feet
50 feet
100 feet
10 feet

NEC Reference: NEC Article 100

Question 7: Equipment that is included on a list published by a qualified testing agency is said to be:

Listed
Grounded
Bonded
Identified only

NEC Reference: NEC Article 100

Question 8: A ground rod must have a minimum length of:

4 feet
6 feet
8 feet
10 feet

NEC Reference: NEC 250.52(A)(5)

Question 9: A service has 1/0 AWG copper ungrounded conductors. What is the minimum copper grounding electrode conductor size?

8 AWG
6 AWG
4 AWG
2 AWG

NEC Reference: NEC 250.66

Question 10: Metal water piping inside a building must be bonded to which of the following?

The service equipment or grounding electrode
Nothing, it does not need bonding
Only the water meter
A nearby fence

NEC Reference: NEC 250.104(A)

Question 11: At each outlet box, at least how much free conductor must be left for splices?

3 inches
6 inches
9 inches
12 inches

NEC Reference: NEC 300.14

Question 12: NM cable (Romex) must be supported and secured at intervals not more than:

2 feet
4 1/2 feet
8 feet
10 feet

NEC Reference: NEC 334.30

Question 13: A cable runs through a hole in a wood stud. If the hole edge is less than 1 1/4 inch from the front of the stud, what must be added?

A steel plate at least 1/16 inch thick
Nothing extra is needed
A layer of paint
A larger hole

NEC Reference: NEC 300.4(A)(1)

Question 14: EMT conduit must be supported at intervals not more than:

5 feet
10 feet
15 feet
20 feet

NEC Reference: NEC 358.30

Question 15: A direct-buried cable is installed with no special cover and is not under a building. What is the general minimum burial depth?

6 inches
12 inches
24 inches
36 inches

NEC Reference: NEC Table 300.5

Question 16: What is the smallest copper conductor allowed for general branch-circuit wiring?

18 AWG
16 AWG
14 AWG
12 AWG

NEC Reference: NEC 310.4

Question 17: Which of the following is a standard fuse and circuit breaker rating listed in the NEC?

22 amperes
25 amperes
28 amperes
32 amperes

NEC Reference: NEC 240.6(A)

Question 18: What is the maximum standard overcurrent device rating for a 14 AWG copper conductor?

15 amperes
20 amperes
25 amperes
30 amperes

NEC Reference: NEC 240.4(D)(3)

Question 19: A service disconnect can have up to how many switches or breakers grouped together?

Four
Six
Eight
Ten

NEC Reference: NEC 230.71(A)

Question 20: What is the minimum rating for the service disconnect of a single-family dwelling?

60 amperes
100 amperes
150 amperes
200 amperes

NEC Reference: NEC 230.79(C)

Question 21: Overhead service conductors must clear a roof by at least how much, in most cases?

3 feet
8 feet
12 feet
18 feet

NEC Reference: NEC 230.24(A)

Question 22: A new receptacle installed on a branch circuit must be:

Grounding type
Non-grounding type
Either type
No type is specified

NEC Reference: NEC 406.4(A)

Question 23: A switch used to control a circuit must be mounted so the handle is no higher than:

5 feet
6 feet 7 inches
8 feet
There is no limit

NEC Reference: NEC 404.8(A)

Question 24: A surface-mounted incandescent light with a fully enclosed bulb is installed in a clothes closet. What clearance is needed from the storage space?

6 inches
12 inches
24 inches
36 inches

NEC Reference: NEC 410.16

Question 25: A motor has a full-load current of 20 amperes. What is the minimum ampacity needed for its branch-circuit conductors?

20 amperes
25 amperes
30 amperes
40 amperes

NEC Reference: NEC 430.22(A)

Question 26: A continuous-duty motor has a normal service factor (less than 1.15). What is the maximum overload protection setting, as a percent of full-load current?

100 %
115 %
125 %
150 %

NEC Reference: NEC 430.32(A)(1)

Question 27: The disconnecting means for an air-conditioning unit must be located:

Within sight of the equipment
Inside the unit, hidden from view
At the main panel only
Anywhere on the property

NEC Reference: NEC 440.14

Question 28: A dry-type transformer rated over 112.5 kVA, installed indoors, must be separated from combustible material by at least:

1 inch
12 inches
6 feet
No separation is needed

NEC Reference: NEC 450.21(A)

Question 29: Class I hazardous locations are divided into which material groups?

Groups A, B, C, and D
Groups 1 and 2 only
Groups E, F, and G
There are no groups

NEC Reference: NEC 500.6(A)

Question 30: Why is an equipotential bonding grid installed around a permanent swimming pool?

To reduce voltage differences and shock risk
To keep the water clean
To support the pool deck
It has no safety purpose

NEC Reference: NEC 680.26(B)

NEC 2020 Code Questions Practice Test 11

How this test works

How to Use This Practice Test

Student Reviews

Leave a Review

NEC 2020 Code Questions Practice Test 11

How this test works

How to Use This Practice Test

Student Reviews

Leave a Review

NEC 2020 Code Questions Practice Test 11 — Question List

Question 1: A panel is rated 120 volts to ground. Live parts are on one side only. What is the minimum working space depth in front of the panel?

Question 2: What is the minimum width of the working space in front of electrical equipment?

Question 3: What is the minimum headroom required for working space around electrical equipment rated 1000 volts or less?

Question 4: Working spaces about service equipment and panelboards must be provided with:

Question 5: Live parts of equipment operating at 50 volts or more must be:

Question 6: Per NEC Article 100, "in sight from" means visible and not more than what distance away?

Question 7: Equipment that is included on a list published by a qualified testing agency is said to be:

Question 8: A ground rod must have a minimum length of:

Question 9: A service has 1/0 AWG copper ungrounded conductors. What is the minimum copper grounding electrode conductor size?

Question 10: Metal water piping inside a building must be bonded to which of the following?

Question 11: At each outlet box, at least how much free conductor must be left for splices?

Question 12: NM cable (Romex) must be supported and secured at intervals not more than:

Question 13: A cable runs through a hole in a wood stud. If the hole edge is less than 1 1/4 inch from the front of the stud, what must be added?

Question 14: EMT conduit must be supported at intervals not more than:

Question 15: A direct-buried cable is installed with no special cover and is not under a building. What is the general minimum burial depth?

Question 16: What is the smallest copper conductor allowed for general branch-circuit wiring?

Question 17: Which of the following is a standard fuse and circuit breaker rating listed in the NEC?

Question 18: What is the maximum standard overcurrent device rating for a 14 AWG copper conductor?

Question 19: A service disconnect can have up to how many switches or breakers grouped together?

Question 20: What is the minimum rating for the service disconnect of a single-family dwelling?

Question 21: Overhead service conductors must clear a roof by at least how much, in most cases?

Question 22: A new receptacle installed on a branch circuit must be:

Question 23: A switch used to control a circuit must be mounted so the handle is no higher than:

Question 24: A surface-mounted incandescent light with a fully enclosed bulb is installed in a clothes closet. What clearance is needed from the storage space?

Question 25: A motor has a full-load current of 20 amperes. What is the minimum ampacity needed for its branch-circuit conductors?

Question 26: A continuous-duty motor has a normal service factor (less than 1.15). What is the maximum overload protection setting, as a percent of full-load current?

Question 27: The disconnecting means for an air-conditioning unit must be located:

Question 28: A dry-type transformer rated over 112.5 kVA, installed indoors, must be separated from combustible material by at least:

Question 29: Class I hazardous locations are divided into which material groups?

Question 30: Why is an equipotential bonding grid installed around a permanent swimming pool?

Related Practice Tests