NEW
Font size
WorksheetsFinal Competition Review Pt. 2
Total questions: 40
Worksheet time: 1hrs 20mins
What are the two main operating functions of a transistor?
To rectify or amplify electrical signals
To amplify or switch electrical signals
To protect or rectify electrical signals
To amplify or protect electrical signals
What are the two main operating functions of a transistor?
To rectify or amplify electrical signals
To amplify or switch electrical signals
To protect or rectify electrical signals
To amplify or protect electrical signals
MCC's often use __________ and __________ transformers to meter and condition voltage and current levels.
buck / boost
control / current
differential / auto
potential / current
? latching relays have a latch coil and an unlatch coil.
Magnetic
Impulse
Mechanical
Pneumatic
All boxes and enclosures for emergency circuits shall be permanently marked so they will be __________ as a component of an emergency circuit or system.
easily recognizable
readily identified
sufficiently evaluated
uniquely distinguishable
What type of transformer has an electrical connection between the primary winding and the secondary winding?
Delta-connected transformer
Potential transformer
Wye-connected transformer
Autotransformer
Ground-fault protection of equipment shall be provided for solidly grounded ? electrical services of more than 150 volts to ground but not exceeding 1,000 volts phase-to-phase for each service disconnect rated 1,000 amperes or more.
delta
industrial
non-dwelling unit
wye
How much voltage is needed for a silicon diode to start conducting when forward-biased?
0.2 V
0.4 V
0.7 V
1.2 V
The converter section of the VFD uses a __________ to convert the incoming AC to a pulsing DC
full-wave bridge rectifier
half-wave bridge rectifier
inductor
transformer
In general, each 1000 volt transformer, nominal, or less, that serve as protection on the primary winding only, shall be protected by an individual overcurrent device on the primary side, rated or set at not more than __________ of the rated primary current of the transformer.
100%
250%
173%
125%
If a 3-phase, single-voltage, wye-connected transformer is supplied by 4,160 volts, the voltage across each winding is ? .
1,680
2,405
4,160
7,197
In wye connected transformers, measured current on A phase is __________ the current on the A phase winding.
0.5 times
0.58 times
1.73 times
equal to
Which of the following is not a type of electrical braking technique used with motors?
Drum braking
Dynamic braking
Injection braking
Regenerative braking
A part-winding starter is only used with a ? motor capable of part-winding starting.
dual-voltage
single-voltage
synchronous
wound-rotor
A continuous load is defined as a load where the maximum current is expected to continue for ? or more.
3 hours
8 hours
1 day
1 week
The polarity of a diode and its condition (open, short) can be checked with a(n) ? .
ammeter
milliammeter
ohmmeter
voltmeter
To prevent an over-torque condition, the operator has to STOP between which of the phases listed?
Elastic and alignment phases
Elastic and plastic phases
Plastic and rundown phases
Rundown and alignment phases
The lead on the left of the device is called the ? .
anode
cathode
Norton Trigger
Schottky trigger
In general, motors shall be located so that adequate ventilation is provided and maintenance, such as lubrication of bearings and ? of brushes, can be readily accomplished.
evaluation
inspection
replacing
servicing
The load power for a buck-boost transformer that boosts the source by 32 volts at a current of 20 amperes is ? .
0.64 kVA
1.60 kVA
640 kVA
1,600 kVA
Wound-rotor motor speed control is accomplished by inserting resistors in series with the ? winding of the motor.
rotor
run
start
stator
In accordance with the requirements of Part III of Article 110, the entrance to all buildings, vaults, rooms, or enclosures containing exposed live parts or exposed conductors shall be kept locked unless such entrances are under the observation of a(n) ? person at all times.
assigned
competent
designated
qualified
The total area of trade size 2 electrical metallic tubing is ? .
2 in2
2.067 in2
3.356 in2
2,165 in2
If six #4 AWG THW copper conductors are installed in the same raceway in an ambient temperature of 30°C, and all of the conductors are current-carrying, what is the ampacity of each of the 4 AWG current-carrying conductors?
42.5 A
68.0 A
85.0 A
106.25 A
A stop-start pushbutton station would have what type of contacts?
1 normally open contact and 1 normally closed contact
2 normally closed contacts
2 normally open contacts
2 normally open contacts and 2 normally closed contacts
The primary leads of a step down transformer are identified with the letter ? .
H
P
S
X
A single winding transformer is more commonly known as a(n) ? .
corner grounded delta transformer
delta-wye transformer
autotransformer
neutral grounded wye transformer
? overload relays may provide phase-loss protection in addition to monitoring motor overload conditions.
Bimetallic
Electronic
Magnetic
Melting alloy
When a feeder supplies continuous loads or any combination of continuous and noncontinuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus ? of the continuous load.
80%
100%
125%
150%
A transformer with more windings on the load side than on the line side is known as a ? transformer.
primary
secondary
step-up
step-down
A lighting panel is protected by 150-ampere non-time delay fuses. What is the minimum size of the aluminum equipment ground?
8 AWG
6 AWG
4 AWG
3 AWG
The approximate area for a 2 AWG THHN insulated copper conductor is ? .
0.02 in2
0.1158 in2
0.384 in2
2 in2
When computing branch-circuit loads, outlets for heavy-duty lampholders shall be computed at a minimum of ? .
15 VA
600 VA
it's rating
the lamp installed
A part-winding starter is only used with a ? motor capable of part-winding starting.
dual-voltage
single-voltage
synchronous
wound-rotor
Which one of the following is not an example of a condition where service conductors shall be considered outside a building or other structure?
Where installed beneath a building or other structure
Where installed in any vault that meets the construction requirements of Article 450, Part III
Where installed in conduit and under not less than 18" of earth beneath a building or other structure
Where installed within a building or other structure in a raceway that is encased in concrete or brick not less than 2" thick
The transformer connections show that the transformer is connected ? .
primary delta - secondary delta
primary delta - secondary wye
primary wye - secondary delta
primary wye - secondary wye
? latching relays have either single or dual coils.
Electronic
Impulse
Magnetic
Mechanical
Transformers use the principle of ? .
mutual hysteresis
mutual impedance
mutual inductance
mutual reactance
Identify the connection types on the transformer.
Primary delta high - secondary delta low
Primary delta high - secondary wye high
Primary delta low - secondary delta low
Primary delta low - secondary wye low
Using the formula for torque, how much force must be applied to a 30-inch long torque wrench to achieve 250 foot-pounds of torque?
10 lbs
82.5 lbs
92 lbs
100 lbs
