Download SACA C-202 ELECTRIC MOTOR CONTROL SYSTEMS QUESTIONS WITH CORRECT ANSWERS 2026 and more Exams Electrical Engineering in PDF only on Docsity!
SACA C-202 ELECTRIC MOTOR
CONTROL SYSTEMS QUESTIONS
WITH CORRECT ANSWERS 2026
Grounding - correct answer-To provide a low-resistance path for fault current, ensuring safety and protecting equipment. Common standards associated with electrical control - correct answer-NEMA, IEC, and NEC standards. Ten basic rules of electrical safety - correct answer-Includes de- energizing circuits, using PPE, verifying lockout/tagout, testing before touch, and using insulated tools, among others. Lockout/tagout system order - correct answer-Notify, shut down, isolate energy, apply LOTO device, release stored energy, and verify zero energy.
Three-phase power operation - correct answer-Three AC voltages 120° out of phase provide continuous power with higher efficiency. Function of neutral in electrical power - correct answer-Serves as a return path for current in unbalanced systems and maintains voltage stability. Using a digital multimeter - correct answer-Set the function (volts, ohms, etc.), connect leads properly, and read measurements. Grounded and ungrounded systems - correct answer-Grounded systems have one conductor connected to ground for safety; ungrounded systems do not, which can delay fault detection. Overcurrent protection devices - correct answer-Fuses melt under excess current; breakers trip; overloads respond to sustained heat or current. Three-phase motor operation - correct answer-Uses rotating magnetic fields from three-phase power to turn the rotor.
Low-voltage protection - correct answer-Shuts off the motor if voltage drops and prevents automatic restart when voltage returns. Types of motor overload devices - correct answer-Thermal (bimetallic), magnetic, and electronic overloads. Motor control and transformer schematic symbols - correct answer-Symbols represent transformer coils, cores, and taps. Operation of transformers - correct answer-Transfers electrical energy between circuits via electromagnetic induction. Turns ratio and secondary voltage of a transformer - correct answer-Secondary voltage = (Primary Voltage) × (Secondary Turns / Primary Turns). Function of an electrical schematic diagram - correct answer- Visually represents how components are connected and function.
Testing a transformer - correct answer-How do you test a transformer? Multimeter - correct answer-Use a multimeter to check for continuity and correct output voltage. Transformer sizing - correct answer-Use the formula: VA = Voltage × Current. Types of electrical control systems - correct answer-Manual, automatic, and semi-automatic systems. Control process steps - correct answer-Input → Logic → Output. Ladder diagram interpretation - correct answer-Understand rungs, logic elements, and power flow left to right.
Three-wire motor control circuit operation - correct answer-Uses momentary pushbuttons (Start/Stop) with holding contacts. Reversing motor control methods - correct answer-Swap any two phases or use reversing contactors. Drum switch operation - correct answer-Mechanically reverses phase connections to reverse motor direction. Motor control circuit interlocking methods - correct answer- Mechanical, electrical (auxiliary contacts), and pushbutton interlocking. Forward/reverse motor jog control circuit - correct answer- Enables brief, manual movement in both directions using momentary contact buttons. Hand-off-automatic motor control circuit interpretation - correct answer-Understand manual/auto modes for user or sensor- controlled starts.
Limit switch operation - correct answer-Opens or closes contacts when an object physically moves the actuator. Float switch function and operation - correct answer-Detects liquid level using a buoyant actuator to open/close electrical contacts. Pressure switch function and operation - correct answer- Opens/closes contacts based on sensed fluid pressure. Relay-based sequence control circuit troubleshooting - correct answer-Understand logic flow and test relay operations. On-delay timer circuit operation - correct answer-Timer delays output activation after coil is energized. Off-delay timer circuit operation - correct answer-Output stays energized for a time after coil is de-energized.
