Cfesa Electrical Exam With 400+ Questions And Detailed Solutions Latest Update This Year

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CFESA ELECTRICAL EXAM WITH 400+ QUESTIONS AND
DETAILED SOLUTIONS LATEST UPDATE THIS YEAR
QUESTION: 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? - ANSWER-.5 amps




QUESTION: 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? - ANSWER-4160 Watts




QUESTION: If you know the wattage and voltage, how do you determine the current? -
ANSWER-Divide the wattage by the voltage




QUESTION: If you know the voltage and current how do you determine the wattage? -
ANSWER-Multiply voltage times current

What do the following prefixes mean? Micro,Kilo,Mega,Milli - ANSWER-1/1,000,000, 1000,
1,000,000, 1/1000

QUESTION: How much voltage is in one hot line? - ANSWER-None




QUESTION: What happens to current in a parallel circuit? - ANSWER-It divides across
resistances




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QUESTION: what happens to voltage across the loads in a parallel circuit? - ANSWER-stays the
same




QUESTION: what happens to the voltage across the loads in a series circuit? - ANSWER-it divides
across the resistances




QUESTION: what happens to the current in a series circuit? - ANSWER-It stays the same
everywhere




QUESTION: in a parallel circuit the total resistance of the circuit will always be less than what
resistance? - ANSWER-the smallest resistance




QUESTION: how do you find the total resistance of a series circuit? - ANSWER-add the
resistances together




QUESTION: how do you find the total resistance of a parallel circuit? - ANSWER-1/RT = 1/R1 +
1/R2 + 1/R3 ...




QUESTION: If a circuit is wired parallel, and the supply voltage is 120 volts, each load must be
rated at what voltage? - ANSWER-120 volts




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QUESTION: 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? -
ANSWER-240 volts




QUESTION: What is the advantage of using higher voltages? - ANSWER-Lower Current and wire
size




QUESTION: Is there a negative and positive line in AC power supplies? - ANSWER-No




QUESTION: What is the voltage between two hot lines in a 230-volt system? - ANSWER-230V




QUESTION: What is the voltage between two hot lines in a 208-volt system? - ANSWER-208V




QUESTION: What is the voltage between a hot line and a neutral in a 230-volt single phase
supply? - ANSWER-115V




QUESTION: What is the voltage between a hot line and a neutral in a 208-volt single phase
supply? - ANSWER-120V




QUESTION: What is the accepted maximum voltage difference between the name plate voltage
and the supplied voltage? - ANSWER-+ or - 10%


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QUESTION: What is the voltage between any two hot lines of a 230 volt delta power supply? -
ANSWER-230V




QUESTION: what is the voltage between a hot line and ground on a 240 volt delta power supply
- ANSWER-No usable voltage




QUESTION: what is the voltage between any two hot lines of a 230 volt grounded delta power
supply - ANSWER-230V




QUESTION: draw a diagram of a 230 volt grounded delta power supply. label all of the voltages
and the wild leg - ANSWER-




QUESTION: what is the wild leg? - ANSWER-leg with higher than 120v to ground or neutral




QUESTION: what danger is the wild leg? - ANSWER-high voltage that will damage 120v
component in the circuit




QUESTION: what is the voltage between either of the non wild leg hot lines and neutral in a 230
volt grounded delta system? - ANSWER-115v




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