Answers.
Which Article of the NEC covers grounding? - Correct Answer article 250
Which of the following is a 90 degree, explosion proof fitting? - Correct Answer GUAL
What is a dropout plate? - Correct 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: -
Correct Answer 372/575 3-PHASE, 4-WIRE
What does a GFCI breaker do? - Correct Answer opens a circuit to prevent operation of
an electrical device
What will happen when one or more coils in a winding are grounded? - Correct 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? - Correct Answer 13.3 amps
The must be grounded in a bussed gutter if used as the main service equipment. -
Correct Answer Neutral bulbar
When wall mounting cable tray, ensure that - Correct 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 - Correct
Answer to keep moisture from creeping in
The outer covering on liquid-tight flexible metal conduit is used for - Correct Answer a
moisture seal
A good electrical connection should - Correct Answer Be mechanically and electrically
secure
The symbol normally used for duplex - Correct Answer Circle with two parallel lines
draw through it
Disconnecting means are covered in - Correct Answer NEC Section 110-22
In relation to switches, the term throw refers to the - Correct Answer Number of internal
operations that a switch can perform
,A 3-phase, 4-wire, 480v service requires ______ current transformer(s) - Correct
Answer 3
Services conductors and equipment are covered in - Correct Answer NEC Article 230
The NEC required that all receptacles installed on 25 amp and 20 amp branch circuits
be ______ receptacles - Correct Answer Grounding
A transformer with the primary of 400 turns and a secondary of 300 turns has a _____ -
Correct Answer Step-down turns ratio of 4:3
The circular mil is based on the - Correct Answer Cross-sectional area of the wire
Of the termination classes listed below, ____ is the only one that provides a seal
against external elements. - Correct Answer Class 1
Unless otherwise noted. The calculations in AC circuits _____ values. - Correct Answer
Rams
When the coil turns are increased the _____ - Correct Answer Induced voltage is
increased
As the temperature surrounding a self-regulating heating cable rises, the ____ - Correct
Answer Resistance of the polymeric core increases
The motor type that has the highest starting torque is the ____ motor. - Correct Answer
Capacitor-start
For a given number of poles, the ____ determines the speed of an AC motor. - Correct
Answer Frequency
Both induction and synchronous motors operate on the principle of a rotating ____ field
- Correct 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: - Correct Answer 90Volts
The output capacity of a motor is rated in - Correct Answer Horsepower
The synchronous speed at which a pole, 60 Hz induction motor operates is rpm. -
Correct Answer 1,800
The sine of 0 degree is - Correct Answer 0
Meters used in AC circuits indicate the - Correct Answer Effective
, The component labeled 7 in figure 1 is a(n) - Correct Answer End seal
In an AC circuit containing resistance only _____ will flow if the resistance is 10 ohms
and the voltage is 120V. - Correct Answer 12A
The _____ rotor types are generally rugged. - Correct Answer Squirrel cage
Proofs tests are made at_ of the original factory voltage. - Correct Answer 60%
Which type of heating cable cannot be cut and terminated in the field? - Correct Answer
Mineral insulated
The secondary of a CT under load should not be opened because of_. - Correct Answer
Induced high voltage
In a transformer ______ - Correct Answer Electromagnetic Induction Ocurs
When a ground rod is installed, the top of the rod must be positioned ______ grade. -
Correct Answer Flush with or below
When making offset bends, the two kicks must be made perfectly parallel or the
resulting offset will have a _____ - Correct 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 _____ - Correct 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 _____ - Correct Answer Undervoltage
conditions
What is the MOST common service used in a temporary power panel? - Correct Answer
120/240 volt, 1-phase, 3-wire
What are the 2 MOST common types of overcurrent protective devices? - Correct
Answer Circuit breakers and fuses
What instrument is used to perform an insulation-resistance test on a 480- volt motor
winding? - Correct Answer Megohmmeter
Why is a seal installed in a run of conduit in a Class I location? - Correct Answer
Prevent the passage of explosive gases in the conduit
Which of the following is the correct formula for OHM's law? - Correct Answer I=E/R
Which of the following testing instruments operated on the current transformer
principle? - Correct Answer Clamp-on ammeter