THE ELECTRICAL NCCER TEST (Electrical Study Guide ) QUESTIONS WITH 100% CORRECT ANSWERS.
Which Article of the NEC covers grounding? Answer- article 250
Which of the following is a 90 degree, explosion proof fitting? Answer- GUAL
What is a dropout plate? Answer- Metal plate with a curved surface for cable to follow as it passes from the tray
All of the following are common service voltages in the United States EXCEPT: Answer- 372/575 3-PHASE, 4-WIRE
What does a GFCI breaker do? Answer- Opens a circuit to prevent operation of an electrical device
What will happen when one or more coils in a winding are grounded? Answer- The motor will automatically blow fuses
Eight incandescent lighting fixtures are to be installed. Each fixture is 120- volts, with
a 200-watt lamp. What is the total connected load? Answer- 13.3 amps
The must be grounded in a bussed gutter if used as the main service equipment. Answer- Neutral busbar
When wall mounting cable tray, ensure that Answer- The building structure is strong
enough to support the tray system
The purpose of sealing cable ends when reels of cable are in storage is Answer- To keep moisture from creeping in
The outer covering on liguid-tight flexible metal conduit is used for Answer- A moisture seal
A good electrical connection should Answer- Be mechanically and electrically secure
The symbol normally used for duplex Answer- Circle with two parallel lines drawb through it Disconnecting means are covered in Answer- NEC Section 110-22
In relation to switches, the term throw refers to the Answer- Number of internal operations that a switch can perform
A 3-phase, 4-wire, 480v service requires ______ current transformer(s) Answer- 3
Services conductors and equipment are covered in Answer- NEC Article 230
The NEC required that all receptacles installed on 25 amp and 20 amp branch circuits be ______ receptacles Answer- Grounding
A transformer with the primary of 400 turns and a secondary of 300 turns has a _____ Answer- Step-down turns ratio of 4:3
The circular mil is based on the Answer- Cross-sectional area of the wire
Of the termination classes listed below, ____ is the only one that provides a seal against external elements. Answer- Class 1
Unless otherwise noted. the calculations in AC circuits _____ values. Answer- Rms
When the coil turns are increased the _____ Answer- Induced voltage is increased
As the temperature surrounding a self-regulating heating cable rises, the ____ Answer- Resistance of the polymeric core increases
The motor type that has the highest starting torque is the ____ motor. Answer- Capacitor-start
For a given number of poles, the ____ determines the speed of an AC motor. Answer- Frequency
Both induction and synchronous motors operate on the principle of a rotating ____ field Answer- Magnetic
A transformer has 200 turns in the primary, 150 turns in the secondary, and 120VAC applied to the primary. The voltage across the secondary is: Answer- 90Volts
The output capacity of a motor is rated in Answer- Horsepower
The synchronous speed at which a pole, 60 Hz induction motor operates is rpm. Answer- 1,800
The sine of 0 degree is Answer- 0
Meters used in AC circuits indicate the Answer- Effective
The component labeled 7 in figure 1 is a(n) Answer- End seal In an AC circuit containing resistance only _____ will flow if the resistance is 10 ohms and the voltage is 120V. Answer- 12A
The _____ rotor types are generally rugged. Answer- Squirrel cage
Proofs tests are made at_ of the original factory voltage. Answer- 60%
Which type of heating cable cannot be cut and terminated in the field? Answer- Mineral insulated
The secondary of a CT under load should not be opened because of_. Answer- Induced high voltage
In a transformer ______ Answer- Electromagnetic Induction Ocurs
When a ground rod is installed, the top of the rod must be positioned ______ grade. Answer- Flush with or below
When making offset bends, the two kicks must be made perfectly parallel or the resulting offset will have a _____ Answer- Crooked Bend
conduit that requires a 90 degree change in direction, except 42.All of the following types of condulet may be used as a pulling point for _____ Answer- C
To be effective, a grounding system must limit the voltage on the electrical system and protect it from all of the following, except _____ Answer- Undervoltage conditions
What is the MOST common service used in a temporary power panel? Answer- 120/240 volt, 1-phase, 3-wire
What are the 2 MOST common types of overcurrent protective devices? Answer- Circuit breakers and fuses
What instrument is used to perform an insulation-resistance test on a 480- volt motor
winding? Answer- Megohmmeter
Why is a seal installed in a run of conduit in a Class I location? Answer- Prevent the passage of explosive gases in the conduit
Which of the following is the correct formula for OHM's law? Answer- I=E/R
Which of the following testing instruments operated on the current transformer principle? Answer- Clamp-on ammeter
A 120/208 volt feeder consists of an 800 ft run of 500 kcmil aluminum wire in conduit.
This feeder has 5% voltage drop. What will the phase-to-phase voltage be at the load end? Answer- 197.60 volts
Which Article of the NEC covers grounding? Answer- article 250
Which of the following is a 90 degree, explosion proof fitting? Answer- GUAL
What is a dropout plate? Answer- Metal plate with a curved surface for cable to follow as it passes from the tray
All of the following are common service voltages in the United States EXCEPT: Answer- 372/575 3-PHASE, 4-WIRE
What does a GFCI breaker do? Answer- Opens a circuit to prevent operation of an electrical device
What will happen when one or more coils in a winding are grounded? Answer- The motor will automatically blow fuses
Eight incandescent lighting fixtures are to be installed. Each fixture is 120- volts, with
a 200-watt lamp. What is the total connected load? Answer- 13.3 amps
The must be grounded in a bussed gutter if used as the main service equipment. Answer- Neutral busbar
When wall mounting cable tray, ensure that Answer- The building structure is strong
enough to support the tray system
The purpose of sealing cable ends when reels of cable are in storage is Answer- To keep moisture from creeping in
The outer covering on liguid-tight flexible metal conduit is used for Answer- A moisture seal
A good electrical connection should Answer- Be mechanically and electrically secure
The symbol normally used for duplex Answer- Circle with two parallel lines drawb through it Disconnecting means are covered in Answer- NEC Section 110-22
In relation to switches, the term throw refers to the Answer- Number of internal operations that a switch can perform
A 3-phase, 4-wire, 480v service requires ______ current transformer(s) Answer- 3
Services conductors and equipment are covered in Answer- NEC Article 230
The NEC required that all receptacles installed on 25 amp and 20 amp branch circuits be ______ receptacles Answer- Grounding
A transformer with the primary of 400 turns and a secondary of 300 turns has a _____ Answer- Step-down turns ratio of 4:3
The circular mil is based on the Answer- Cross-sectional area of the wire
Of the termination classes listed below, ____ is the only one that provides a seal against external elements. Answer- Class 1
Unless otherwise noted. the calculations in AC circuits _____ values. Answer- Rms
When the coil turns are increased the _____ Answer- Induced voltage is increased
As the temperature surrounding a self-regulating heating cable rises, the ____ Answer- Resistance of the polymeric core increases
The motor type that has the highest starting torque is the ____ motor. Answer- Capacitor-start
For a given number of poles, the ____ determines the speed of an AC motor. Answer- Frequency
Both induction and synchronous motors operate on the principle of a rotating ____ field Answer- Magnetic
A transformer has 200 turns in the primary, 150 turns in the secondary, and 120VAC applied to the primary. The voltage across the secondary is: Answer- 90Volts
The output capacity of a motor is rated in Answer- Horsepower
The synchronous speed at which a pole, 60 Hz induction motor operates is rpm. Answer- 1,800
The sine of 0 degree is Answer- 0
Meters used in AC circuits indicate the Answer- Effective
The component labeled 7 in figure 1 is a(n) Answer- End seal In an AC circuit containing resistance only _____ will flow if the resistance is 10 ohms and the voltage is 120V. Answer- 12A
The _____ rotor types are generally rugged. Answer- Squirrel cage
Proofs tests are made at_ of the original factory voltage. Answer- 60%
Which type of heating cable cannot be cut and terminated in the field? Answer- Mineral insulated
The secondary of a CT under load should not be opened because of_. Answer- Induced high voltage
In a transformer ______ Answer- Electromagnetic Induction Ocurs
When a ground rod is installed, the top of the rod must be positioned ______ grade. Answer- Flush with or below
When making offset bends, the two kicks must be made perfectly parallel or the resulting offset will have a _____ Answer- Crooked Bend
conduit that requires a 90 degree change in direction, except 42.All of the following types of condulet may be used as a pulling point for _____ Answer- C
To be effective, a grounding system must limit the voltage on the electrical system and protect it from all of the following, except _____ Answer- Undervoltage conditions
What is the MOST common service used in a temporary power panel? Answer- 120/240 volt, 1-phase, 3-wire
What are the 2 MOST common types of overcurrent protective devices? Answer- Circuit breakers and fuses
What instrument is used to perform an insulation-resistance test on a 480- volt motor
winding? Answer- Megohmmeter
Why is a seal installed in a run of conduit in a Class I location? Answer- Prevent the passage of explosive gases in the conduit
Which of the following is the correct formula for OHM's law? Answer- I=E/R
Which of the following testing instruments operated on the current transformer principle? Answer- Clamp-on ammeter
A 120/208 volt feeder consists of an 800 ft run of 500 kcmil aluminum wire in conduit.
This feeder has 5% voltage drop. What will the phase-to-phase voltage be at the load end? Answer- 197.60 volts
