Electrical Controls Technician Practice Exam
Questions With Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. What is the primary function of a motor starter?
A. Increase voltage
B. Protect against lightning
C. Control motor starting and stopping
D. Convert AC to DC
Correct Answer: C
Rationale: A motor starter safely starts and stops a motor and
provides overload protection.
2. Which device protects a circuit from overcurrent conditions?
A. Transformer
B. Fuse
C. Relay coil
D. Motor contactor
Correct Answer: B
Rationale: A fuse melts when excessive current flows, protecting
the circuit.
3. A normally open (NO) contact means:
A. It is always closed
B. It closes when energized
, C. It is always open
D. It opens when energized
Correct Answer: B
Rationale: NO contacts close when the control circuit is energized.
4. What does a control transformer do?
A. Converts mechanical energy
B. Steps down voltage for control circuits
C. Amplifies current
D. Stores energy
Correct Answer: B
Rationale: Control transformers reduce voltage for safe control
circuit operation.
5. Which component provides overload protection in motor circuits?
A. Contactor
B. Thermal overload relay
C. Capacitor
D. Diode
Correct Answer: B
Rationale: Thermal overload relays protect motors from
overheating.
6. A ladder diagram is primarily used for:
A. Plumbing systems
B. Electrical control circuits
C. Hydraulic systems
D. Mechanical drawings
Correct Answer: B
Rationale: Ladder diagrams represent electrical control logic.
, 7. What is the function of a relay?
A. Increase resistance
B. Provide switching using an electromagnet
C. Store electricity
D. Reduce current
Correct Answer: B
Rationale: Relays use electromagnets to open or close contacts.
8. In a DC circuit, polarity refers to:
A. Resistance level
B. Direction of current flow
C. Wire thickness
D. Temperature
Correct Answer: B
Rationale: DC circuits have fixed current direction (polarity).
9. What does PLC stand for?
A. Power Line Converter
B. Programmable Logic Controller
C. Primary Load Circuit
D. Parallel Logic Control
Correct Answer: B
Rationale: PLCs are industrial computers used for automation.
10. Which device is used to manually start or stop a motor?
A. Limit switch
B. Pushbutton
C. Relay coil
D. Transformer
Questions With Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. What is the primary function of a motor starter?
A. Increase voltage
B. Protect against lightning
C. Control motor starting and stopping
D. Convert AC to DC
Correct Answer: C
Rationale: A motor starter safely starts and stops a motor and
provides overload protection.
2. Which device protects a circuit from overcurrent conditions?
A. Transformer
B. Fuse
C. Relay coil
D. Motor contactor
Correct Answer: B
Rationale: A fuse melts when excessive current flows, protecting
the circuit.
3. A normally open (NO) contact means:
A. It is always closed
B. It closes when energized
, C. It is always open
D. It opens when energized
Correct Answer: B
Rationale: NO contacts close when the control circuit is energized.
4. What does a control transformer do?
A. Converts mechanical energy
B. Steps down voltage for control circuits
C. Amplifies current
D. Stores energy
Correct Answer: B
Rationale: Control transformers reduce voltage for safe control
circuit operation.
5. Which component provides overload protection in motor circuits?
A. Contactor
B. Thermal overload relay
C. Capacitor
D. Diode
Correct Answer: B
Rationale: Thermal overload relays protect motors from
overheating.
6. A ladder diagram is primarily used for:
A. Plumbing systems
B. Electrical control circuits
C. Hydraulic systems
D. Mechanical drawings
Correct Answer: B
Rationale: Ladder diagrams represent electrical control logic.
, 7. What is the function of a relay?
A. Increase resistance
B. Provide switching using an electromagnet
C. Store electricity
D. Reduce current
Correct Answer: B
Rationale: Relays use electromagnets to open or close contacts.
8. In a DC circuit, polarity refers to:
A. Resistance level
B. Direction of current flow
C. Wire thickness
D. Temperature
Correct Answer: B
Rationale: DC circuits have fixed current direction (polarity).
9. What does PLC stand for?
A. Power Line Converter
B. Programmable Logic Controller
C. Primary Load Circuit
D. Parallel Logic Control
Correct Answer: B
Rationale: PLCs are industrial computers used for automation.
10. Which device is used to manually start or stop a motor?
A. Limit switch
B. Pushbutton
C. Relay coil
D. Transformer
