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Property & Building Inspection

Electrical practice questions

10 original sample questions on electrical. Pick an answer, then open the explanation. Review the electrical study notes first if you like.

1. A GFCI breaker is identified by:

  1. A test button
  2. A larger size
  3. A red handle
  4. Two poles only
Show answer & explanation

Answer: A. A test button

GFCI breakers have test buttons.

2. 12 AWG copper branch circuit conductors are typically protected by a breaker of:

  1. 30 amps
  2. 40 amps
  3. 50 amps
  4. 20 amps
Show answer & explanation

Answer: D. 20 amps

Common sizing: 14 AWG copper on 15 A, 12 AWG on 20 A, 10 AWG on 30 A.

3. 14 AWG copper wire on a 30-amp breaker indicates:

  1. A breaker that is too small
  2. A ground fault on the circuit
  3. Correct sizing for heavy loads
  4. Overcurrent protection exceeds wire capacity
Show answer & explanation

Answer: D. Overcurrent protection exceeds wire capacity

14 AWG copper is usually limited to 15 amps.

4. A GFCI device protects people by detecting:

  1. Loose connections that arc in walls
  2. Overloaded circuits drawing high current at startup
  3. Voltage spikes from lightning
  4. Current imbalance between hot and neutral
Show answer & explanation

Answer: D. Current imbalance between hot and neutral

GFCIs trip on small leakage current. (General reference: NEC 210.8 (GFCI protection); local adoption varies.)

5. A 'double-tapped' breaker means:

  1. Two breakers are tied together with a handle tie
  2. A breaker that serves outlets in two different rooms
  3. Two conductors are under a terminal designed for only one
  4. A breaker has tripped twice
Show answer & explanation

Answer: C. Two conductors are under a terminal designed for only one

Most breakers are listed for one conductor. Two can loosen and overheat, so report it as a defect.

6. A bedroom circuit lacks AFCI protection in a home built in the 1980s. The best report statement is:

  1. Older homes cannot have AFCI breakers installed
  2. AFCI not present; consider upgrade for added safety
  3. The circuit is defective and must be disconnected now
  4. AFCI is required by law in every older home immediately
Show answer & explanation

Answer: B. AFCI not present; consider upgrade for added safety

AFCIs may not have been required when built; recommend as a safety upgrade. (General reference: NEC 210.12 (AFCI protection); local adoption varies.)

7. A burned smell or scorched receptacle indicates:

  1. Normal operation under load
  2. Dust burning off a new device
  3. Overheating and a fire hazard
  4. New paint drying on the plate
Show answer & explanation

Answer: C. Overheating and a fire hazard

Report heat damage.

8. A double-pole breaker serves a 240-volt water heater with one handle tripped and the other on. This most likely indicates:

  1. Normal operation of a 240-volt circuit breaker
  2. The water heater uses 120 volts on each side
  3. The breaker is a GFCI type that has been tested
  4. A breaker that is not common-trip; evaluate
Show answer & explanation

Answer: D. A breaker that is not common-trip; evaluate

Two-pole breakers should trip both legs together.

9. A ceiling fan that wobbles badly should be:

  1. Removed by the inspector
  2. Ignored since it still spins
  3. Reported for securing
  4. Painted in place
Show answer & explanation

Answer: C. Reported for securing

Loose fans can fall.

10. A main panel with a 200 A main fed by 2 AWG aluminum conductors may be:

  1. Ideal for heavy loads
  2. Undersized for the rating
  3. Correctly grounded
  4. Oversized for the breaker rating
Show answer & explanation

Answer: B. Undersized for the rating

Conductors must match the rating.

Original practice items for study only, not actual exam questions. Content may contain errors.