Nccer Electrical level 3 mod 9 Exam
Questions And Answers
3 basic types of 3ø motors -
correct answer ✅Synchronous motor
Wound rotor induction
Squirrel cage induction
3 factors that cause the magnetic field to rotate -
correct answer ✅The voltages of a 3ø electrical system are 120°
out of phase with one another
The three voltages change polarity at regular intervals
The stator windings around the inside of the motor are arranged in
a specific manner to induced rotation
They sync speed of 3 phase motor is based on 2 factors -
correct answer ✅Number of stator poles
Frequency of the ac line in hertz
The formula for sync speed is -
correct answer ✅120F divided by P
, Nccer Electrical level 3 mod 9 Exam
Questions And Answers
F= -
correct answer ✅Frequency
P= -
correct answer ✅Number of poles
When a motor is operated at 240 volts the current draw of the
motor is ___ the current draw of a 480 volt connection -
correct answer ✅Double
I= -
correct answer ✅E/R
Multiply the full load current of the largest motor ___ then add the
sum of the remaining motors to the result. The combined total will
give the minimum feeder ampacity -
correct answer ✅1.25
The motor horse power is shown in the far left column of -
correct answer ✅Table 430.250
Questions And Answers
3 basic types of 3ø motors -
correct answer ✅Synchronous motor
Wound rotor induction
Squirrel cage induction
3 factors that cause the magnetic field to rotate -
correct answer ✅The voltages of a 3ø electrical system are 120°
out of phase with one another
The three voltages change polarity at regular intervals
The stator windings around the inside of the motor are arranged in
a specific manner to induced rotation
They sync speed of 3 phase motor is based on 2 factors -
correct answer ✅Number of stator poles
Frequency of the ac line in hertz
The formula for sync speed is -
correct answer ✅120F divided by P
, Nccer Electrical level 3 mod 9 Exam
Questions And Answers
F= -
correct answer ✅Frequency
P= -
correct answer ✅Number of poles
When a motor is operated at 240 volts the current draw of the
motor is ___ the current draw of a 480 volt connection -
correct answer ✅Double
I= -
correct answer ✅E/R
Multiply the full load current of the largest motor ___ then add the
sum of the remaining motors to the result. The combined total will
give the minimum feeder ampacity -
correct answer ✅1.25
The motor horse power is shown in the far left column of -
correct answer ✅Table 430.250
