HVAC Electrical Test Questions and Answers Rated A
Current flow is the flow of electrons in the circuit
impedance is opposition to alternating current flow
like charges repel each other
Any material that will readily release electrons is called a conductor
the symbol for current is I
Which of the following materials would best be suited for
silicone
use as a semi-conductor
the safety ground conductor is usually color coded black (or bare or green & yellow stripe)
An electron has a negative charge
resistance is opposition to current flow
How many watts of power are used by a heater operating
2300 watts
at 460 volts and drawing 5 amps?
What type of meter uses its own battery? ohmmeter
in electrical wiring a black colored wire usually indicates the hot conductor
Fuses are sized by Volts & Amps
Two 120 volt incandescent light bulbs are wired in series,
one is a 60 watt bulb, the other is a 4 watt bulb. The result Both bulbs light
would be;
Three defrost heaters; each 15 ohms are wired in parallel
to a 120 volt power supply. How many watts of power will 2880 watts
be used?
What is generally considered to be the maximum allow-
5%
able (plus or minus) supply voltage variation?
Capacitors are rated in: Microfarads & Volts
When testing a capacitor with an analog ohmmeter, the
deflect towards zero then return to infinite reading.
needle on the meter should;
1/7
, HVAC Electrical Test Questions and Answers Rated A
What is the term used to describe the output side of a
Secondary side
transformer?
One horsepower is equal to how many watts? 746 Watts
How much resistance must be placed in a 120 volt circuit
60 ohms
in order to limit the current to 2 amps?
A parallel circuit contains a 18 ohm and 9 ohm resistor. The
6 ohms
total resistance equals;
In a series circuit, the voltage drop across each resistance
Add up to equal the source voltage
(load) will;
The total resistance of a parallel circuit will be; Less than the smallest resistance
Which of the following statements about current is true? Current flow will increase when voltage increases.
The voltage drop across each resistor will be the same as
When resistors are wired in parallel;
the applied source voltage.
Which of the following is equal to 2.1KW? 2,100 Watts
Which of the following is equal to 100 milliamps? 0.10 amperes
A capacitor analyzer is designed to read; the capacitance of a capacitor
A 240 volt, 3 wire circuit can be split into two 120 volt
TRUE
circuits.
The electric meter on a house measures the
wattage
passing through it.
A three phase load requires a minimum of; three supply lines
Which of the following is the correct formula for determin-
W = E times I (or V x I)
ing wattage in an electrical circuit?
A parallel circuit consists of three resistors
R1=30 ohms R2=15 ohms R3=10ohms
60 volts
if the current through R2=4 amperes, what is the source
voltage?
2/7
Current flow is the flow of electrons in the circuit
impedance is opposition to alternating current flow
like charges repel each other
Any material that will readily release electrons is called a conductor
the symbol for current is I
Which of the following materials would best be suited for
silicone
use as a semi-conductor
the safety ground conductor is usually color coded black (or bare or green & yellow stripe)
An electron has a negative charge
resistance is opposition to current flow
How many watts of power are used by a heater operating
2300 watts
at 460 volts and drawing 5 amps?
What type of meter uses its own battery? ohmmeter
in electrical wiring a black colored wire usually indicates the hot conductor
Fuses are sized by Volts & Amps
Two 120 volt incandescent light bulbs are wired in series,
one is a 60 watt bulb, the other is a 4 watt bulb. The result Both bulbs light
would be;
Three defrost heaters; each 15 ohms are wired in parallel
to a 120 volt power supply. How many watts of power will 2880 watts
be used?
What is generally considered to be the maximum allow-
5%
able (plus or minus) supply voltage variation?
Capacitors are rated in: Microfarads & Volts
When testing a capacitor with an analog ohmmeter, the
deflect towards zero then return to infinite reading.
needle on the meter should;
1/7
, HVAC Electrical Test Questions and Answers Rated A
What is the term used to describe the output side of a
Secondary side
transformer?
One horsepower is equal to how many watts? 746 Watts
How much resistance must be placed in a 120 volt circuit
60 ohms
in order to limit the current to 2 amps?
A parallel circuit contains a 18 ohm and 9 ohm resistor. The
6 ohms
total resistance equals;
In a series circuit, the voltage drop across each resistance
Add up to equal the source voltage
(load) will;
The total resistance of a parallel circuit will be; Less than the smallest resistance
Which of the following statements about current is true? Current flow will increase when voltage increases.
The voltage drop across each resistor will be the same as
When resistors are wired in parallel;
the applied source voltage.
Which of the following is equal to 2.1KW? 2,100 Watts
Which of the following is equal to 100 milliamps? 0.10 amperes
A capacitor analyzer is designed to read; the capacitance of a capacitor
A 240 volt, 3 wire circuit can be split into two 120 volt
TRUE
circuits.
The electric meter on a house measures the
wattage
passing through it.
A three phase load requires a minimum of; three supply lines
Which of the following is the correct formula for determin-
W = E times I (or V x I)
ing wattage in an electrical circuit?
A parallel circuit consists of three resistors
R1=30 ohms R2=15 ohms R3=10ohms
60 volts
if the current through R2=4 amperes, what is the source
voltage?
2/7
