Journeyman Electrician Practice Test 16

Question 1: A separate disconnecting means is not required for a motor with a power rating of 1/8 HP or less.

• True
• False

Question 2: A concealed conductor in electrical wiring means:

• Rendered inaccessible by the structure or finish of the building
• Easily accessible conductor
• A conductor run on the surface of a wall or ceiling
• A conductor having no cover

Question 3: A Electric water heater consumes 16 ampere from a 240 volt branch circuit. what is the minimum ampere rating of branch circuit?

• 20 amperes
• 25 amperes
• 30 amperes
• 16 amperes

Question 4: If a time delay fuse is used as short circuit protection of a motor, what is the maximum allowed rating of fuse?

• 125 % of the ampere rating of motor
• 175 % of the ampere rating of motor
• 250 % of the ampere rating of motor

Question 5: What is the minimum distance that a service drop wires should maintain if it is placed above commercial places?

• 10 ft
• 12 ft
• 15 ft
• 18 ft

NEC Reference: NEC 230.24

Question 6: Which of the following is the equation used to calculate the voltage drop in a resistor according to Kirchhoff’s voltage law?

• IR
• I/R
• R/I
• I²R

Question 7: Load shared by two transformers connected in parallel will depend upon their ......................

• efficiency
• rating
• per unit impedance
• input frequency

Question 8: The slip of induction motor is always ..................

• between zero and unity
• less than zero
• more than unity

Question 9: The overhead conductors between last pole of power company and building structure used for electrical service are termed as …………..

• Service entrance
• Service drop
• Service head
• Service entrance conductors

Question 10: The leakage flux in  a transformer depends upon .........................

• mutual flux
• supply frequency
• load current

Question 11: What percentage of rated current is the distribution transformer no load current?

• 2 to 5%
• 5 to 10%
• 15 to 30%

Question 12: Plug fuses of Edison-base type shall be used for only …………………

• Replacement for existing installations
• External protection to bus bar
• Motor control panel
• Control circuit protection unit

NEC Reference: NEC 240.51(B)

Question 13: The pendant conductors longer than ……….. in length to be twisted together.

• 4 feet
• 3 feet
• 5 feet
• 2 feet

NEC Reference: NEC 410.54(C)

Question 14: Which of the following instrument is used to measure the resistance in the circuit directly?

• Ammeter
• Volt meter
• Watt meter
• Ohm meter

Question 15: If a 30 amperes snap switch is used as disconnecting means of a 3-horse power motor, what shall be the maximum full load current of the motor?

• 24 amperes
• 30 amperes
• 18 amperes
• 28 amperes

NEC Reference: NEC 430.109(C)(2)

Question 16: What is the advantage of a Type S (rejection-type) fuse over an Edison-base fuse?

• It has a faster melting time
• It cannot be replaced with a higher ampere-rated fuse
• It is cheaper than an Edison-base fuse
• It works only on AC circuits

NEC Reference: NEC 240.53

Question 17: Which type of fuse opens faster during an overload condition?

• Time-delay (slow-blow) fuse
• Non-time-delay (fast-blow) fuse
• Both open at the same speed
• Speed depends only on fuse size, not type

Question 18: Which of the following is NOT a standard overcurrent device rating listed in NEC 240.6(A)?

• 15 amperes
• 30 amperes
• 22 amperes
• 50 amperes

NEC Reference: NEC 240.6(A)

Question 19: In a standard single-phase 3-wire service (120/240V), what is the voltage between the two hot (ungrounded) conductors?

• 120 volts
• 208 volts
• 240 volts
• 480 volts

Question 20: When sizing conductors and overcurrent protection for a motor, which values should be used for full-load current?

• The nameplate full-load amperes (FLA)
• The values from NEC Tables 430.247–430.250
• The locked-rotor amperes from the nameplate
• The service factor times the horsepower

NEC Reference: NEC 430.6(A)(1)

Question 21: What is the purpose of a service head (weatherhead) at the top of the service entrance?

• To measure incoming voltage
• To prevent rain from entering the service entrance conduit
• To ground the service entrance conductors
• To connect the utility meter to the panel

Question 22: When a feeder supplies multiple motors, how must the feeder ampacity be calculated?

• Sum of all motor full-load currents only
• 125% of the largest motor FLC + sum of all other motor FLCs
• 100% of the largest motor only
• 125% of all motor FLCs added together

NEC Reference: NEC 430.24

Question 23: When conductors of different circuits are installed in the same conduit, what insulation requirement applies?

• Each conductor may have its own minimum insulation rating
• All conductors must be rated for the highest voltage in the conduit
• Only the hot conductors need higher insulation
• Conduit provides insulation so wire rating does not matter

NEC Reference: NEC 300.3(C)(1)

Question 24: What is the minimum headroom (height) required in the working space above electrical equipment rated 600V or less?

• 5 feet
• 6 feet
• 6.5 feet
• 7 feet

NEC Reference: NEC 110.26(E)

Question 25: In a Class I, Division 1 hazardous location, what type of electrical equipment must be used?

• Standard indoor equipment with extra covers
• Explosion-proof or intrinsically safe equipment
• Weatherproof NEMA 3R equipment
• GFCI-protected standard equipment

NEC Reference: NEC 501.10(A)

Question 26: If a motor disconnect is NOT within sight of the motor, what additional requirement applies?

• No additional requirement — sight-of-motor rule does not apply
• The disconnect must be capable of being locked in the open (OFF) position
• A second disconnect must be installed at the motor
• The motor must have a built-in thermal cutout

NEC Reference: NEC 430.102(B)

Question 27: What is the maximum number of service disconnecting means (breakers or switches) allowed per service at one location?

• 2
• 4
• 6
• 10

NEC Reference: NEC 230.71(A)

Question 28: According to NEC Article 100, what does "within sight" mean as used in motor disconnect rules?

• Visible and not more than 25 feet away
• Visible and not more than 50 feet away
• Visible and not more than 100 feet away
• In the same room regardless of distance

NEC Reference: NEC 100

Question 29: After a motor overload relay trips, how must it normally be reset?

• It automatically resets after the motor cools down
• It must be manually reset by a person
• The utility company must be called to reset it
• It resets after a time delay of 30 seconds

NEC Reference: NEC 430.43

Question 30: A motor controller that is not within sight of the motor it controls must .............

• Be within 10 feet of the motor
• Have a disconnect that can be locked in the open (OFF) position
• Be connected directly to the motor terminals
• No special requirement — any controller can be anywhere

NEC Reference: NEC 430.87