CFESA ELECTRICAL EXAM ACTUAL QUESTION BANK
COMPLETE 200+ QUESTIONS AND CORRECT
DETAILED ANSWERS – LATEST UPDATE THIS YEAR
JUST RELEASED
What do the following prefixes mean? Micro,Kilo,Mega,Milli -
..(answers)..1/1,000,000, 1000, 1,000,000, 1/1000
If you know the wattage and voltage, how do you determine the current? -
..(answers)..Divide the wattage by the voltage
If you know the voltage and current how do you determine the wattage? -
..(answers)..Multiply voltage times current
If a circuit is supplied with 100 volts and the total resistance of the circuit is 200
ohms, how much current will the circuit draw? - ..(answers)...5 amps
If a piece of equipment is supplied 208 volts and the amp meter clamped to the
hot line reads 20 amps, what is the wattage of the load? - ..(answers)..4160 Watts
How much voltage is in one hot line? - ..(answers)..None
What happens to current in a parallel circuit? - ..(answers)..It divides across
resistances
,what happens to voltage across the loads in a parallel circuit? - ..(answers)..stays
the same
what happens to the voltage across the loads in a series circuit? - ..(answers)..it
divides across the resistances
what happens to the current in a series circuit? - ..(answers)..It stays the same
everywhere
in a parallel circuit the total resistance of the circuit will always be less than what
resistance? - ..(answers)..the smallest resistance
how do you find the total resistance of a series circuit? - ..(answers)..add the
resistances together
how do you find the total resistance of a parallel circuit? - ..(answers)..1/RT = 1/R1
+ 1/R2 + 1/R3 ...
If a circuit is wired parallel, and the supply voltage is 120 volts, each load must be
rated at what voltage? - ..(answers)..120 volts
if a circuit has two elements wired in series, and each is rated at 120 volts, what
voltage must be supplied to the circuit in order for the elements to heat at full
power? - ..(answers)..240 volts
,What is the advantage of using higher voltages? - ..(answers)..Lower Current and
wire size
Is there a negative and positive line in AC power supplies? - ..(answers)..No
What is the voltage between two hot lines in a 230-volt system? -
..(answers)..230V
What is the voltage between two hot lines in a 208-volt system? -
..(answers)..208V
What is the voltage between a hot line and a neutral in a 230-volt single phase
supply? - ..(answers)..115V
What is the voltage between a hot line and a neutral in a 208-volt single phase
supply? - ..(answers)..120V
What is the accepted maximum voltage difference between the name plate
voltage and the supplied voltage? - ..(answers)..+ or - 10%
What is the voltage between any two hot lines of a 230 volt delta power supply? -
..(answers)..230V
, what is the voltage between a hot line and ground on a 240 volt delta power
supply - ..(answers)..No usable voltage
what is the voltage between any two hot lines of a 230 volt grounded delta power
supply - ..(answers)..230V
draw a diagram of a 230 volt grounded delta power supply. label all of the
voltages and the wild leg - ..(answers)..
what is the wild leg? - ..(answers)..leg with higher than 120v to ground or neutral
what danger is the wild leg? - ..(answers)..high voltage that will damage 120v
component in the circuit
what is the voltage between either of the non wild leg hot lines and neutral in a
230 volt grounded delta system? - ..(answers)..115v
how do you determine which hot line is the wild leg in a 250 volt grounded delta
power supply? - ..(answers)..the one that does not measure 120 volts to neutral
or ground
what danger is there when replacing a three phase circuit breaker in a 230 volt
grounded delta power supply? - ..(answers)..crossing the hot lines and supplying
the wild leg to the wrong terminal in the unit.
COMPLETE 200+ QUESTIONS AND CORRECT
DETAILED ANSWERS – LATEST UPDATE THIS YEAR
JUST RELEASED
What do the following prefixes mean? Micro,Kilo,Mega,Milli -
..(answers)..1/1,000,000, 1000, 1,000,000, 1/1000
If you know the wattage and voltage, how do you determine the current? -
..(answers)..Divide the wattage by the voltage
If you know the voltage and current how do you determine the wattage? -
..(answers)..Multiply voltage times current
If a circuit is supplied with 100 volts and the total resistance of the circuit is 200
ohms, how much current will the circuit draw? - ..(answers)...5 amps
If a piece of equipment is supplied 208 volts and the amp meter clamped to the
hot line reads 20 amps, what is the wattage of the load? - ..(answers)..4160 Watts
How much voltage is in one hot line? - ..(answers)..None
What happens to current in a parallel circuit? - ..(answers)..It divides across
resistances
,what happens to voltage across the loads in a parallel circuit? - ..(answers)..stays
the same
what happens to the voltage across the loads in a series circuit? - ..(answers)..it
divides across the resistances
what happens to the current in a series circuit? - ..(answers)..It stays the same
everywhere
in a parallel circuit the total resistance of the circuit will always be less than what
resistance? - ..(answers)..the smallest resistance
how do you find the total resistance of a series circuit? - ..(answers)..add the
resistances together
how do you find the total resistance of a parallel circuit? - ..(answers)..1/RT = 1/R1
+ 1/R2 + 1/R3 ...
If a circuit is wired parallel, and the supply voltage is 120 volts, each load must be
rated at what voltage? - ..(answers)..120 volts
if a circuit has two elements wired in series, and each is rated at 120 volts, what
voltage must be supplied to the circuit in order for the elements to heat at full
power? - ..(answers)..240 volts
,What is the advantage of using higher voltages? - ..(answers)..Lower Current and
wire size
Is there a negative and positive line in AC power supplies? - ..(answers)..No
What is the voltage between two hot lines in a 230-volt system? -
..(answers)..230V
What is the voltage between two hot lines in a 208-volt system? -
..(answers)..208V
What is the voltage between a hot line and a neutral in a 230-volt single phase
supply? - ..(answers)..115V
What is the voltage between a hot line and a neutral in a 208-volt single phase
supply? - ..(answers)..120V
What is the accepted maximum voltage difference between the name plate
voltage and the supplied voltage? - ..(answers)..+ or - 10%
What is the voltage between any two hot lines of a 230 volt delta power supply? -
..(answers)..230V
, what is the voltage between a hot line and ground on a 240 volt delta power
supply - ..(answers)..No usable voltage
what is the voltage between any two hot lines of a 230 volt grounded delta power
supply - ..(answers)..230V
draw a diagram of a 230 volt grounded delta power supply. label all of the
voltages and the wild leg - ..(answers)..
what is the wild leg? - ..(answers)..leg with higher than 120v to ground or neutral
what danger is the wild leg? - ..(answers)..high voltage that will damage 120v
component in the circuit
what is the voltage between either of the non wild leg hot lines and neutral in a
230 volt grounded delta system? - ..(answers)..115v
how do you determine which hot line is the wild leg in a 250 volt grounded delta
power supply? - ..(answers)..the one that does not measure 120 volts to neutral
or ground
what danger is there when replacing a three phase circuit breaker in a 230 volt
grounded delta power supply? - ..(answers)..crossing the hot lines and supplying
the wild leg to the wrong terminal in the unit.
