Free Electrician Practice Test

In an above-ground conduit run, may conductors be spliced inside the conduit between boxes?

• ANo, splices are generally required to be in a box, conduit body, or other approved enclosure
• BYes, if the conduit is EMT
• CYes, if the conductors are THHN
• DNo, unless the conduit is PVC

A 120-volt, single-phase, 20-amp branch circuit supplies a receptacle in a dwelling unit laundry area. What protection is required?

• ABoth AFCI and GFCI protection
• BAFCI protection only
• CGFCI protection only
• DOnly a standard breaker

If resistance increases in a circuit while voltage remains constant, current will:

• ADecrease
• BIncrease
• CRemain unchanged
• DBecome zero

A required bathroom receptacle is mounted on the face of the vanity cabinet. It must be located no more than how far below the top of the basin countertop?

• A6 in.
• B18 in.
• C20 in.
• D12 in.

What does the “W” in THWN or THWN-2 MOST directly indicate?

• ASuitable for wet locations
• BSuitable for welding use
• CSuitable for wall cavities only
• DSuitable for wireways only

An EVSE has a maximum load of 24 amps on its 240-volt supply circuit. No permitted adjustment changes the rating used. What is the MINIMUM overcurrent protective device rating?

• A30A
• B25A
• C24A
• D20A

Which NEC section addresses guarding of live parts to prevent accidental contact (such as equipment in accessible areas)?

• A110.27
• B110.26
• C240.24
• D90.4

In a grounded separately derived AC system, the derived grounded conductor must be:

• ABonded to the equipment bonding path by a system bonding jumper at a single point, from the source through the first disconnecting means
• BBonded at every downstream panel
• CLeft ungrounded
• DConnected to equipment grounding conductors only

In a grounded utility service with one service disconnect, the grounded (neutral) conductor is bonded to the service enclosure primarily to:

• AEstablish the grounded conductor connection at a single point and provide an effective fault current path
• BEliminate the need for equipment grounding conductors downstream
• CAllow neutral current to flow on all metal raceways intentionally
• DReduce arc-faults in branch circuits

A disconnect is installed in a mechanical room with several identical disconnects in a row. Each is marked only with a number (1, 2, 3) with no legend or schedule. This is MOST likely:

• ANot compliant because the purpose is not indicated
• BCompliant because each disconnect has a unique number
• CCompliant if the numbers match the panel schedule somewhere else
• DCompliant if the disconnects are within sight of the equipment

An MWBC is installed with the neutral passing through device terminals (not pigtailed). A receptacle is removed later and the neutral opens. What is the MOST likely outcome?

• AUnstable voltage on 120V loads and possible equipment damage due to neutral shift
• BEverything becomes safely de-energized automatically
• COnly the equipment grounding conductor carries current safely
• DThe breaker rating increases to compensate

A problem states: “THHN copper in a raceway longer than 24 in., ambient 40°C, 6 current-carrying conductors.” Which items are needed to solve it correctly?

• ABase ampacity table + temperature correction table + CCC adjustment table + termination limits
• BOnly the base ampacity table
• COnly the conduit fill tables
• DOnly the grounding electrode conductor table

For a land area not subject to tidal fluctuation, such as a lake shore, the electrical datum plane is the horizontal plane how far above the highest water level that occurs under normal circumstances?

• A2 ft
• B6 in.
• C12 in.
• D5 ft

A single internal cable clamp (built into the box) counts as:

• AOne conductor volume allowance, based on the largest conductor present in the box
• BZero conductor volume allowance
• CTwo conductor volume allowances
• DOne allowance for each cable entering the box

A generator supplies both emergency loads and an optional standby panel. The installer uses one transfer switch to serve both the emergency and optional standby loads. What is the main defect?

• AEmergency transfer equipment must supply only emergency loads
• BThe generator must be 3-phase
• CThe neutral must always be switched
• DThe equipment grounding conductor must be aluminum

An ordinary motor starter or contactor controls a motor. Under 430.83(A)(1), its rating must be:

• AA horsepower rating, at the application voltage, not lower than the motor's horsepower
• BThe same as the feeder conductor size
• CExactly the same as the service disconnect rating
• DAlways larger than the branch-circuit breaker rating

According to NEC Article 100, "Overcurrent" is best described as:

• AAny current in excess of the rated current of equipment or the ampacity of a conductor
• BCurrent that flows only during a short circuit
• CCurrent caused only by a ground-fault condition
• DCurrent that exceeds the service disconnect rating only

Which item is MOST directly about bonding (not grounding)?

• AConnecting metal raceways and enclosures together to ensure electrical continuity
• BDriving ground rods to connect the system to earth
• CSizing the grounding electrode conductor to a UFER
• DInstalling a surge protective device at the service

Which article covers Class II locations involving combustible dust?

• AArticle 502
• BArticle 501
• CArticle 503
• DArticle 250

A series circuit has three resistors: 2 Ω, 3 Ω, and 5 Ω on a 10 V source. What is the total current?

• A1 A
• B2 A
• C0.5 A
• D10 A