TPC ELECTRICAL LEVEL 3 TEST
Questions and Answers Latest Versions
2025 GRADED A+
If a motor stops for no apparent reason and you are called to inspect the
motor starter, the first thing you should check is the
• control transformer
• insulation around the contactor coil
• limit switch
• trip levers on the thermal overload relays Right Ans - trip levers on the
thermal overload relays
In an induction motor, maximum torque is always developed when the
• impedance has a lagging phase angle
• phase angle is 60
• power factor is 50%
• reactance and the resistance of the rotor are equal Right Ans - reactance
and the resistance of the rotor are equal
A _____ switch is used for changing a control circuit from one sequence to
another.
• drum
• foot
• plugging
• transfer Right Ans - foot
Overvoltage, excessive current and too-frequent operation are possible causes
of
• burned or short-circuited magnet coils
• contacts that do not close when the START button is pressed
,• fuse blowing when the START button is pressed
• noisy magnet operation Right Ans - contacts that do not close when the
START button is pressed
In which of the following motors does torque vary inversely with speed?
• Constant horsepower
• Constant torque
• Variable horsepower
• Variable torque Right Ans - constant horsepower
Thermal overload relays can generally be reset after cooling for about
• 1 minute
• 15 minute
• 30 minute
• 1 hour Right Ans - 1 minute
Many electric motors are manufactured according to standards set by
• NEMA
• OEM
• NFPA
• OSHA Right Ans - NEMA
Operating a heavily loaded motor at ____can cause high slip.
• a reduced power factor
• increased voltage
• reduced current
• reduced voltage Right Ans - reduced voltage
A computer can function like a PLC if you provide a way for the computer to
receive signals from what?
• other PLCs
• inputs
• outputs
• other computers Right Ans - outputs
, The grounding conductor connected to a grounding plug is
• black
• green
• red
• white Right Ans - green
Reduced-voltage starters for three-phase motors change the potential
difference across the motor by means of
• autotransformers or resistors
• capacitors or autotransformers
• overload relays or capacitors
• resistors or overload relays Right Ans - autotransformers or resistors
DC motors and generators have ____ which cause special problems not
normally found in ac machines.
• commutators and brushes
• pole-phase groups
• split phases
• windings Right Ans - commutators and brushes
Float switches are used for controlling all of the following EXCEPT
• motor starters
• small motors
• temperature-maintaining equipment
• valves Right Ans - temperature-maintaining equipment
Which data files are the most fundamental?
• relay registers
• I/O registers
• reserve files
• general purpose files Right Ans - I/O registers
Questions and Answers Latest Versions
2025 GRADED A+
If a motor stops for no apparent reason and you are called to inspect the
motor starter, the first thing you should check is the
• control transformer
• insulation around the contactor coil
• limit switch
• trip levers on the thermal overload relays Right Ans - trip levers on the
thermal overload relays
In an induction motor, maximum torque is always developed when the
• impedance has a lagging phase angle
• phase angle is 60
• power factor is 50%
• reactance and the resistance of the rotor are equal Right Ans - reactance
and the resistance of the rotor are equal
A _____ switch is used for changing a control circuit from one sequence to
another.
• drum
• foot
• plugging
• transfer Right Ans - foot
Overvoltage, excessive current and too-frequent operation are possible causes
of
• burned or short-circuited magnet coils
• contacts that do not close when the START button is pressed
,• fuse blowing when the START button is pressed
• noisy magnet operation Right Ans - contacts that do not close when the
START button is pressed
In which of the following motors does torque vary inversely with speed?
• Constant horsepower
• Constant torque
• Variable horsepower
• Variable torque Right Ans - constant horsepower
Thermal overload relays can generally be reset after cooling for about
• 1 minute
• 15 minute
• 30 minute
• 1 hour Right Ans - 1 minute
Many electric motors are manufactured according to standards set by
• NEMA
• OEM
• NFPA
• OSHA Right Ans - NEMA
Operating a heavily loaded motor at ____can cause high slip.
• a reduced power factor
• increased voltage
• reduced current
• reduced voltage Right Ans - reduced voltage
A computer can function like a PLC if you provide a way for the computer to
receive signals from what?
• other PLCs
• inputs
• outputs
• other computers Right Ans - outputs
, The grounding conductor connected to a grounding plug is
• black
• green
• red
• white Right Ans - green
Reduced-voltage starters for three-phase motors change the potential
difference across the motor by means of
• autotransformers or resistors
• capacitors or autotransformers
• overload relays or capacitors
• resistors or overload relays Right Ans - autotransformers or resistors
DC motors and generators have ____ which cause special problems not
normally found in ac machines.
• commutators and brushes
• pole-phase groups
• split phases
• windings Right Ans - commutators and brushes
Float switches are used for controlling all of the following EXCEPT
• motor starters
• small motors
• temperature-maintaining equipment
• valves Right Ans - temperature-maintaining equipment
Which data files are the most fundamental?
• relay registers
• I/O registers
• reserve files
• general purpose files Right Ans - I/O registers
