test3 elec principles study guide
All insulations perform equally well in dry, damp, and wet locations.
False
What meter measures an amount of voltage during a period of time and produces a two-dimensional image?
an oscilloscope
A test meter that uses a scale and pointer to indicate values is a(n) _____ meter.
analog
Several cells connected together that produce voltage are called a _____.
battery
One of the most common devices used to measure values of resistance, inductance, and capacitance accurately is a(n) _______________ circuit.
bridge
The meter is only connected to one of the lines supplying power when using a(n) _____ ammeter.
clamp-on
The amount of energy a cell can deliver is called its _____ capacity.
current
Moving coil meter is another name for the _____ meter movement.
d'Arsonval
The transformer that converts a high voltage from the power company down to 240/120 V for homes and businesses is called a(n) _____ transformer.
distribution
What is the maximum current (amperes) that should be applied when charging an 80-ampere-hour battery?
eight
In a transformer, even when there is no load connected, there will be some small current flow known as _____ current.
excitation
Any transformer flux that does not follow the core and escapes into the surrounding air is called _____.
flux leakage
A voltmeter has a very _____ resistance connected in series with the meter movement.
high
The series ohmmeter is used to measure _____ values of resistance.
high
he low-impedance voltage tester is most suitable for use in _____.
high power circuits
A device used for measuring the specific gravity of a cell is called a _____.
hydrometer
What is the nonconductive covering around a wire?
insulation
A transformer in which the primary and secondary are physically separated and not connected by a conductor is called a(n) _____ transformer.
isolation
Most transformer cores are assembled from many thin sheets of metal. This type of construction is called _____.
laminated
When the connection of a meter to the circuit changes the entire circuit operation, this is known as the _____ effect.
loading
The insulation used on conductors cannot operate in all possible temperatures. The highest allowable temperature is called the _____ temperature.
maximum operating
To test wire insulation, a special type of ohmmeter called a(n) _____ is used.
megger
A(n) _____ ammeter operates on more than one range by connecting the meter movement to different shunts.
multirange
Most voltmeters are _____ voltmeters, meaning they are designed to use one meter movement to measure several ranges.
multirange
When a conductor is very large it may become necessary to connect them in _____
parallel
The no-load voltage of a cell is greater than the normal load voltage because of the internal _____ of the cell.
resistance
What is measured by the Wheatstone bridge?
resistance
The output winding of a transformer is called the _____ winding.
secondary
What type of cell can be recharged?
secondary
Solar cells are constructed from a combination of P- and N-type _____ materials
semiconductor
An ammeter is connected in _____ with the load to permit the load to limit current flow.
series
What is a measure of the amount of acid contained in water?
specific gravity
A transformer in which the secondary voltage is more than the primary voltage is called a(n) _____ transformer.
step-up
The ambient air temperature considered in relation to a conductor ampacity is the temperature of the _____.
surrounding air
Thermocouples produce voltage because of the action of two dissimilar metals. The voltage produced depends on the type of metals used and the _____ difference between the junction and the open ends.
temperature
In the American Engineers Handbook, the standard temperature of material resistance is _____.
20 celsius
Nickel-cadmium (nicad) cells can be charged and discharged about _____ times.
2000
If there are more than _____ conductors in a raceway, the ampacity of the conductors must be derated.
3
What is the terminal voltage of a nicad battery containing six cells?
7.2
The ampacities listed in Table 310.15(B)(16) are based on an ambient temperature of _____.
86F
The ____________________ was standardized in 1857 and is used mainly in the United States for the diameters of round, solid, nonferrous electrical wire.
AWG
What meter measures true power in a circuit?
Wattmeter
What meter features a wire coil suspended between permanent magnet poles and operates on very tiny amounts of current?
a galvanometer
An ammeter has a typical impedance of less than _______________ ohm
0.1
To perform a load test on a lead-acid battery, the amount of test current should be _____ times the ampere-hour capacity.
3
The National Electrical Code® _____ contains tables dealing with conductors for general wiring
310
What is a magnetically operated device that can change values of voltage, current, and impedance without changing frequency?
a transformer
A voltaic cell is constructed of two unlike metals and a(n) _____, alkaline, or salt solution.
acid
In the National Electrical Code®, the current carrying abilities of conductors are called the _____.
ampacities
What meter measures resistance?
an ohmmeter
A transformer that has one winding, which is used for both the primary and secondary, is called a(n) _____.
autotransformer
The word _____ is often used in reference to a single cell.
battery
There are six current-carrying conductors in a raceway that is to be installed in an area with an ambient temperature of 90°F. It is necessary to
correct for temperature and derate (because of the number of conductors)
The ampacities listed in the tables are based on a specified ambient temperature. If conductors are to be operated in a different ambient temperature than the temperature specified, a(n) ____________________ factor must be applied.
correction
What is one of the most common analog meter movements?
d'Arsonval movement
A list of metals showing their willingness to accept electrons is called the _____ series of metals.
electromotive
What meter must NEVER be connected to a circuit when the circuit power is turned on?
ohmmeter
There are two conductors, a red and a blue installed in metallic conduit. You are using a MEGGER to test for shorts. How should the two leads of the MEGGER should be connected?
one to the blue lead and one to the red lead
Materials that increase their resistance with an increase in temperature have a _____ coefficient of temperature
positive
Piezoelectricity refers to electricity produced by some materials when they are subjected to _____.
pressure
The power input winding of a transformer is called the _____ winding.
primary
The longer the conductor, the more _____ it will have.
resistance
A low-resistance device used to conduct most circuit current away from the meter movement is an ammeter _____.
shunt
A transformer in which the secondary voltage is less than the primary voltage is called a(n) _____ transformer
step-down
In 1800, Alessandro Volta was experimenting with producing electricity. He called his battery _____.
voltaic pile
What meter is designed to be connected directly across the power source?
voltmeter
A tape-wound core is also called a(n) _____ core.
toroid
Most of the electric power in the world is produced by alternators.
true
In a transformer, the turns of primary wire compared to the turns of secondary wire is called the _____ ratio.
turns
A tape-wound core is assembled by _____.
winding a long continuous tape into a spiral
A piece of wire that is one mil in diameter and one foot long is one mil-foot.
True
An isolation transformer has the same input and output voltages.
True
The unit circular mil is equal to the _____.
diameter of the wire in mils squared
The amount of current that flows into a transformer primary when voltage is first applied is called _____ current.
inrush
What type of core is often found on high-voltage distribution transformers?
H-Type
The LeClanché cell is also known as a(n) _____ cell.
carbon-zinc
The amount of voltage produced by an individual _____ is determined by the materials from which it is made.
cell
What type of cell cannot be recharged?
primary
A shunt device that remains connected to the meter movement and thereby eliminates contact resistance problems is the _______________ shunt.
Ayrton
The resistors are connected in parallel with the meter on some ranges and in series for other ranges when a(n) _____ is used.
Ayrton shunt
There are two conductors, a red and a blue installed in metallic conduit. You are using a MEGGER to test for grounds. How should the two leads of the MEGGER should be connected?
BOTH (one to the blue lead and one to the conduit/ one to the red lead and one to the conduit)
The d'Arsonval meter movement is operated by applying _____ current to the coil.
DC
