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SACA C-202 ELECTRIC MOTOR CONTROL SYSTEMS
ACTUAL EXAM Questions 200 | 100% Pass
Guaranteed | Graded A+
[1] What is the primary function of a motor control system?
A. To convert mechanical energy into electrical energy
B. To supply raw power to a motor without regulation
C. To start, stop, protect, and control the speed or direction of an electric motor
D. To measure the resistance of motor windings
☑ Correct Answer: C
☑ Explanation: A motor control system is designed to safely start, stop, protect, and in
many cases control the speed or direction of an electric motor. Options A and D describe
functions of generators and testing equipment, respectively, while B describes an unregulated
power supply.
[2] Which law states that the current through a conductor is directly proportional to the voltage
across it and inversely proportional to its resistance?
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A. Faraday's Law
B. Lenz's Law
C. Kirchhoff's Voltage Law
D. Ohm's Law
☑ Correct Answer: D
☑ Explanation: Ohm's Law (V = IR) states that current is directly proportional to voltage
and inversely proportional to resistance. It is a fundamental principle used throughout motor
control circuit analysis. Faraday's Law relates to electromagnetic induction, Lenz's Law to
induced current direction, and Kirchhoff's Voltage Law to voltage drops in a closed loop.
[3] A motor nameplate reads 460V, 3-phase, 60 Hz, 20 HP. What is the approximate full-load
current (FLC)?
A. 10 A
B. 16 A
C. 24 A
D. 32 A
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☑ Correct Answer: C
☑ Explanation: Using the formula I = (HP × 746) / (√3 × V × η × PF), a 20 HP, 460V, 3-phase
motor typically draws approximately 24 A at full load, consistent with NEC Table 430.250 values.
[4] Which component in a motor control circuit provides overload protection?
A. Fuse
B. Circuit breaker
C. Contactor
D. Overload relay
☑ Correct Answer: D
☑ Explanation: The overload relay monitors motor current and trips when excessive
current is detected over time, protecting the motor from thermal damage due to overloading.
Fuses and circuit breakers protect against short circuits, not sustained overloads.
[5] What does NEMA stand for in the context of motor standards?
A. National Electrical Manufacturers Association
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B. National Energy Management Authority
C. North American Electrical Motor Assembly
D. National Equipment Maintenance Association
☑ Correct Answer: A
☑ Explanation: NEMA stands for National Electrical Manufacturers Association. It
develops standards for electrical equipment including motors, enclosures, and control devices
used throughout North America.
[6] In a three-phase induction motor, what is the relationship between synchronous speed and
the number of poles?
A. Speed increases as poles increase
B. Speed is independent of poles
C. Speed decreases as poles increase
D. Speed doubles with every additional pole pair
SACA C-202 ELECTRIC MOTOR CONTROL SYSTEMS
ACTUAL EXAM Questions 200 | 100% Pass
Guaranteed | Graded A+
[1] What is the primary function of a motor control system?
A. To convert mechanical energy into electrical energy
B. To supply raw power to a motor without regulation
C. To start, stop, protect, and control the speed or direction of an electric motor
D. To measure the resistance of motor windings
☑ Correct Answer: C
☑ Explanation: A motor control system is designed to safely start, stop, protect, and in
many cases control the speed or direction of an electric motor. Options A and D describe
functions of generators and testing equipment, respectively, while B describes an unregulated
power supply.
[2] Which law states that the current through a conductor is directly proportional to the voltage
across it and inversely proportional to its resistance?
,2
A. Faraday's Law
B. Lenz's Law
C. Kirchhoff's Voltage Law
D. Ohm's Law
☑ Correct Answer: D
☑ Explanation: Ohm's Law (V = IR) states that current is directly proportional to voltage
and inversely proportional to resistance. It is a fundamental principle used throughout motor
control circuit analysis. Faraday's Law relates to electromagnetic induction, Lenz's Law to
induced current direction, and Kirchhoff's Voltage Law to voltage drops in a closed loop.
[3] A motor nameplate reads 460V, 3-phase, 60 Hz, 20 HP. What is the approximate full-load
current (FLC)?
A. 10 A
B. 16 A
C. 24 A
D. 32 A
,3
☑ Correct Answer: C
☑ Explanation: Using the formula I = (HP × 746) / (√3 × V × η × PF), a 20 HP, 460V, 3-phase
motor typically draws approximately 24 A at full load, consistent with NEC Table 430.250 values.
[4] Which component in a motor control circuit provides overload protection?
A. Fuse
B. Circuit breaker
C. Contactor
D. Overload relay
☑ Correct Answer: D
☑ Explanation: The overload relay monitors motor current and trips when excessive
current is detected over time, protecting the motor from thermal damage due to overloading.
Fuses and circuit breakers protect against short circuits, not sustained overloads.
[5] What does NEMA stand for in the context of motor standards?
A. National Electrical Manufacturers Association
, 4
B. National Energy Management Authority
C. North American Electrical Motor Assembly
D. National Equipment Maintenance Association
☑ Correct Answer: A
☑ Explanation: NEMA stands for National Electrical Manufacturers Association. It
develops standards for electrical equipment including motors, enclosures, and control devices
used throughout North America.
[6] In a three-phase induction motor, what is the relationship between synchronous speed and
the number of poles?
A. Speed increases as poles increase
B. Speed is independent of poles
C. Speed decreases as poles increase
D. Speed doubles with every additional pole pair
