CFESA ELECTRICAL CORRECT
QUESTIONS & ANSWERS|| 2025 LATEST
UPDATE|| 100% VERIFIED
What do the following prefixes mean? Micro,Kilo,Mega,Milli - ANSWER 1/1,000,000,
1000, 1,000,000, 1/1000
If you know the wattage and voltage, how do you determine the current? - ANSWER
Divide the wattage by the voltage
If you know the voltage and current how do you determine the wattage? - ANSWER
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? - ANSWER .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? - ANSWER 4160 Watts
How much voltage is in one hot line? - ANSWER None
What happens to current in a parallel circuit? - ANSWER It divides across resistances
what happens to voltage across the loads in a parallel circuit? - ANSWER stays the
same
what happens to the voltage across the loads in a series circuit? - ANSWER it divides
across the resistances
what happens to the current in a series circuit? - ANSWER It stays the same
everywhere
in a parallel circuit the total resistance of the circuit will always be less than what
resistance? - ANSWER the smallest resistance
how do you find the total resistance of a series circuit? - ANSWER add the resistances
together
how do you find the total resistance of a parallel circuit? - ANSWER 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? - ANSWER 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? -
ANSWER 240 volts
What is the advantage of using higher voltages? - ANSWER Lower Current and wire
size
Is there a negative and positive line in AC power supplies? - ANSWER No
What is the voltage between two hot lines in a 230-volt system? - ANSWER 230V
What is the voltage between any hot line and neutral or ground in a 208 volt WYE
power supply? - ANSWER 120v
What is the voltage from any hot line to ground or neutral, on a 480 volt WYE power
supply? - ANSWER 277v
if you had a commercial building and you had a three phase supply to your building how
many different incoming power supplies would you need if the incoming three phase
supply was three phase delta? - ANSWER 2
if you had a commercial building and you had a three phase supply to your building,
how many different incoming power supplies would you need if the incoming three
phase supply was three phase grounded delta? - ANSWER 1
if you had a commercial building and you had a three phase supply to your building how
many different incoming power supplies would you need if the incoming three phase
supply was three phase WYE 208v? - ANSWER 1
approximately how much will the wattage increase on a 208v piece of equipment if it is
connected to 240v supply? - ANSWER 33%
approximately how much will the rated wattage decrease if a 240v unit is connected to a
208v power supply? - ANSWER 25%
what damage could potentially be caused to the supply wiring if 208v unit is connected
to a 240v supply? - ANSWER higher wattage created will damage heaters or other
components
how can the cooking characteristics of equipment be changed by a low supply voltage?
- ANSWER slow recovery time, uneven cooking
when is the most opportune time to discover a low or high voltage problem? - ANSWER
at equipment startup, before the unit is energized
,can high voltage result in and overheating problem when trying to control the temp of an
oven? - ANSWER yes
how many resistances must you have to have a balanced load? - ANSWER 3 or a
multiple of 3
what is the formula for calculating the current draw from the wattage and voltage on a
three phase balanced load? - ANSWER amperage = wattage / (voltage X 1.732)
how can you tell if a piece of equipment will be a balanced load or not? - ANSWER
must have 3 or a multiple of three loads
Joe says a convection oven that has three heating elements, and a single phase blower
motor is a balanced three phase load. Jim says it is not. Who is right? - ANSWER Jim,
the single phase motor unbalances the load
Electricity will always follow what path? - ANSWER Path of least resistance
Why should all equipment be grounded? - ANSWER safety and code
How should the earth ground from the main fuse or breaker panel be connected? -
ANSWER from grounding bus bar to ground rod or metal water pipe
in order for a receptacle to be properly grounded, the ground wire must run to where? -
ANSWER all the way back to the panel
How much resistance should you read from a neutral connection to a ground
connection? - ANSWER 0 ohms
What is the difference between neutral and ground? - ANSWER the neatural normall
carries current, the ground does not
Can you get shocked from the casing on a piece of equipment if it is properly grounded?
- ANSWER No
Ground wires must always be what colors? - ANSWER green, green with yellow tracer,
or bare white
How much current does a short circuit draw? - ANSWER Infinite Amps
if a cord on a unit is shorted, can it damage the power switch on the piece of
equipment? - ANSWER No
if a heating element on an electric grill is shorted could it damage the thermostat? -
ANSWER Yes
, If a power switch is shorted on a heat lamp could it damage the heating element? -
ANSWER No
When checking voltage, you must touch your meter leads where? - ANSWER Across
the load you are measuring
If you check each side of an element terminal to ground and you read 120 volts, does
that mean that the element has voltage to it? - ANSWER No
Which conductor can carry a higher current if they are the same gauge, copper or
nickel? - ANSWER Copper
What. conductor material is used for high temp wire applications? - ANSWER nickel or
nickel tinned copper
What is the advantage of nickel tinned copper wire? - ANSWER handles high temp and
higher current than nickel
What are the two major downfalls of pure nickel wire? - ANSWER cost, and lower
current capacity
what is TGGT wire made of? - ANSWER nickel tinned copper wire, teflon insulated with
fiberglass braid
What is MGS wire made of? - ANSWER Nickel tinned copper, mica insulated with
fiberglass braid
which wire should be used on a pizza oven operating at 650 degrees? - ANSWER MGS
What is special about SO or SJO cord that makes it desirable in the commercial food
service industry? - ANSWER Grease and oil resistant
Ground wires must always be what color(s)? - ANSWER Green, green with yellow
tracer, or bare metal
Neutral wire(s) must always be what color? - ANSWER White
what size THHN wire should be used for a 20 amp load? - ANSWER 12 gauge
What size TGGT wire should be used for a 30 amp load? - ANSWER 12 gauge
What size SO cord should be used for a 40 amp load? - ANSWER 8 gauge
Give three common reasons for wire failures - ANSWER undersized, temp rating too
low, poor connections
QUESTIONS & ANSWERS|| 2025 LATEST
UPDATE|| 100% VERIFIED
What do the following prefixes mean? Micro,Kilo,Mega,Milli - ANSWER 1/1,000,000,
1000, 1,000,000, 1/1000
If you know the wattage and voltage, how do you determine the current? - ANSWER
Divide the wattage by the voltage
If you know the voltage and current how do you determine the wattage? - ANSWER
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? - ANSWER .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? - ANSWER 4160 Watts
How much voltage is in one hot line? - ANSWER None
What happens to current in a parallel circuit? - ANSWER It divides across resistances
what happens to voltage across the loads in a parallel circuit? - ANSWER stays the
same
what happens to the voltage across the loads in a series circuit? - ANSWER it divides
across the resistances
what happens to the current in a series circuit? - ANSWER It stays the same
everywhere
in a parallel circuit the total resistance of the circuit will always be less than what
resistance? - ANSWER the smallest resistance
how do you find the total resistance of a series circuit? - ANSWER add the resistances
together
how do you find the total resistance of a parallel circuit? - ANSWER 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? - ANSWER 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? -
ANSWER 240 volts
What is the advantage of using higher voltages? - ANSWER Lower Current and wire
size
Is there a negative and positive line in AC power supplies? - ANSWER No
What is the voltage between two hot lines in a 230-volt system? - ANSWER 230V
What is the voltage between any hot line and neutral or ground in a 208 volt WYE
power supply? - ANSWER 120v
What is the voltage from any hot line to ground or neutral, on a 480 volt WYE power
supply? - ANSWER 277v
if you had a commercial building and you had a three phase supply to your building how
many different incoming power supplies would you need if the incoming three phase
supply was three phase delta? - ANSWER 2
if you had a commercial building and you had a three phase supply to your building,
how many different incoming power supplies would you need if the incoming three
phase supply was three phase grounded delta? - ANSWER 1
if you had a commercial building and you had a three phase supply to your building how
many different incoming power supplies would you need if the incoming three phase
supply was three phase WYE 208v? - ANSWER 1
approximately how much will the wattage increase on a 208v piece of equipment if it is
connected to 240v supply? - ANSWER 33%
approximately how much will the rated wattage decrease if a 240v unit is connected to a
208v power supply? - ANSWER 25%
what damage could potentially be caused to the supply wiring if 208v unit is connected
to a 240v supply? - ANSWER higher wattage created will damage heaters or other
components
how can the cooking characteristics of equipment be changed by a low supply voltage?
- ANSWER slow recovery time, uneven cooking
when is the most opportune time to discover a low or high voltage problem? - ANSWER
at equipment startup, before the unit is energized
,can high voltage result in and overheating problem when trying to control the temp of an
oven? - ANSWER yes
how many resistances must you have to have a balanced load? - ANSWER 3 or a
multiple of 3
what is the formula for calculating the current draw from the wattage and voltage on a
three phase balanced load? - ANSWER amperage = wattage / (voltage X 1.732)
how can you tell if a piece of equipment will be a balanced load or not? - ANSWER
must have 3 or a multiple of three loads
Joe says a convection oven that has three heating elements, and a single phase blower
motor is a balanced three phase load. Jim says it is not. Who is right? - ANSWER Jim,
the single phase motor unbalances the load
Electricity will always follow what path? - ANSWER Path of least resistance
Why should all equipment be grounded? - ANSWER safety and code
How should the earth ground from the main fuse or breaker panel be connected? -
ANSWER from grounding bus bar to ground rod or metal water pipe
in order for a receptacle to be properly grounded, the ground wire must run to where? -
ANSWER all the way back to the panel
How much resistance should you read from a neutral connection to a ground
connection? - ANSWER 0 ohms
What is the difference between neutral and ground? - ANSWER the neatural normall
carries current, the ground does not
Can you get shocked from the casing on a piece of equipment if it is properly grounded?
- ANSWER No
Ground wires must always be what colors? - ANSWER green, green with yellow tracer,
or bare white
How much current does a short circuit draw? - ANSWER Infinite Amps
if a cord on a unit is shorted, can it damage the power switch on the piece of
equipment? - ANSWER No
if a heating element on an electric grill is shorted could it damage the thermostat? -
ANSWER Yes
, If a power switch is shorted on a heat lamp could it damage the heating element? -
ANSWER No
When checking voltage, you must touch your meter leads where? - ANSWER Across
the load you are measuring
If you check each side of an element terminal to ground and you read 120 volts, does
that mean that the element has voltage to it? - ANSWER No
Which conductor can carry a higher current if they are the same gauge, copper or
nickel? - ANSWER Copper
What. conductor material is used for high temp wire applications? - ANSWER nickel or
nickel tinned copper
What is the advantage of nickel tinned copper wire? - ANSWER handles high temp and
higher current than nickel
What are the two major downfalls of pure nickel wire? - ANSWER cost, and lower
current capacity
what is TGGT wire made of? - ANSWER nickel tinned copper wire, teflon insulated with
fiberglass braid
What is MGS wire made of? - ANSWER Nickel tinned copper, mica insulated with
fiberglass braid
which wire should be used on a pizza oven operating at 650 degrees? - ANSWER MGS
What is special about SO or SJO cord that makes it desirable in the commercial food
service industry? - ANSWER Grease and oil resistant
Ground wires must always be what color(s)? - ANSWER Green, green with yellow
tracer, or bare metal
Neutral wire(s) must always be what color? - ANSWER White
what size THHN wire should be used for a 20 amp load? - ANSWER 12 gauge
What size TGGT wire should be used for a 30 amp load? - ANSWER 12 gauge
What size SO cord should be used for a 40 amp load? - ANSWER 8 gauge
Give three common reasons for wire failures - ANSWER undersized, temp rating too
low, poor connections
