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ELECTRICAL SUPERVISOR (BS-16) Complete Preparation Guide & Solved Questions (2026) - Apex Rankers

NTS Recruitment Examination Syllabus & Question Bank

6519 Total Questions
~9779 mins Read Time
4 Subject Areas
🎯 High-Yield Preparation Strategy

📘 Official Examination Scheme, Question Blueprint & Interview Masterclass

✓ 100% Comprehensive Guide

Official Written Examination Blueprint & Master Preparation Guide

Candidate Selection Architecture for ELECTRICAL SUPERVISOR (BS-16)

📋 1. Examination Scheme & Marking Blueprint

The competitive recruitment screening for ELECTRICAL SUPERVISOR (BS-16) consists of a single-paper 100-mark Multiple Choice Question (MCQ) written examination evaluating Practical Electrical & Power Systems, Quantitative Aptitude Test, English Language Comprehension, and General Knowledge. The assessment duration is standardized at 90 minutes. A strict qualifying benchmark of 50% aggregate marks is mandatory for merit consideration. Negative marking is applied at a rate of 0.25 marks deducted per incorrect response, requiring candidates to exercise disciplined accuracy during question selection. Top-merit qualifiers are shortlisted for panel interview scrutiny at a ratio of 1:5 against announced vacancies.

Examination Subject / Question Type Target Marks Weightage Cognitive Focus & Syllabus Benchmark
Practical Electrical & Power Systems 50 MCQs 50% HVAC & Refrigeration Cycles, Electrical Distribution & Protection Relays, Motor Controls & Wiring Standards, Industrial Troubleshooting
Quantitative Aptitude Test 20 MCQs 20% Arithmetic calculations, algebra, geometric reasoning, quantitative problem solving
English Language Comprehension 15 MCQs 15% Grammar rules, sentence structuring, vocabulary, reading comprehension
General Knowledge 15 MCQs 15% World affairs, international organizations, geography, everyday facts

💡 2. High-Yield Conceptual Problem Solving & Case Scenarios

Mastery of applied operational problems is essential for securing top-tier percentiles. The following high-yield case scenarios reflect actual operational scenarios encountered in competitive selection exams:

Scenario 1: Authentic Practical Scenario 1 for Electrical Supervisor

Operational Dilemma: An electrical fault has been reported in the port's loading dock area. Describe the steps you would take to identify and resolve the issue.

💡 Model Answer & Protocol: First, conduct a visual inspection of the affected area. Then, use diagnostic tools to pinpoint the exact location of the fault. After identifying the issue, replace or repair the faulty component. Finally, perform a thorough test to ensure the system is working correctly.
Standard: Adherence to safety protocols and compliance with electrical safety standards.
Scenario 2: Authentic Practical Scenario 2 for Electrical Supervisor

Operational Dilemma: How would you handle a situation where a critical electrical system fails during a busy port operation?

💡 Model Answer & Protocol: Prioritize safety by evacuating personnel and securing the area. Then, assess the extent of the failure and determine the quickest way to restore power. Coordinate with other departments to minimize disruption and ensure a swift resolution.
Standard: Quick thinking and adherence to emergency procedures.
Scenario 3: Authentic Practical Scenario 3 for Electrical Supervisor

Operational Dilemma: You have been tasked with upgrading the port's electrical infrastructure. Outline your approach to this project.

💡 Model Answer & Protocol: Conduct a needs assessment to identify areas for improvement. Develop a detailed plan with timelines and budgets. Engage with stakeholders to gather feedback and secure necessary approvals. Implement the upgrade plan while ensuring minimal disruption to operations.
Standard: Project management skills and adherence to electrical installation standards.

🎯 3. Departmental Selection Board Viva Voce & Panel Interview

Candidates shortlisted after the written screening will appear before a 3 to 5 member Departmental Selection Board. Interviews evaluate professional mastery, situational integrity, and knowledge of official rules.

Q1: What are the key safety standards you follow when performing electrical maintenance?
Model Response: I follow OSHA and IEC standards, which include using personal protective equipment, testing for voltage before touching circuits, and ensuring proper grounding.
Q2: Can you describe a time when you had to troubleshoot a complex electrical issue?
Model Response: During a recent incident, I used diagnostic tools to identify a faulty relay. I replaced it and conducted a series of tests to ensure the system was functioning properly. The issue was resolved without any downtime.
Q3: How do you ensure that your team adheres to safety protocols?
Model Response: I conduct regular safety briefings and drills. I also enforce a culture of safety by leading by example and addressing any non-compliance immediately.
Q4: What steps would you take if you discovered a potential electrical hazard in the port?
Model Response: I would first isolate the area to prevent further damage or injury. Then, I would report the issue to my superiors and coordinate with the safety department to address the hazard promptly.

📅 4. 14-Day Strategic Revision Roadmap

Execute this structured two-week study plan to consolidate syllabus coverage and peak cognitive readiness:

  • Days 1-5: Practical Electrical & Power Systems Mastery: Cover core theoretical foundations, statutory frameworks, technical standards, and high-frequency past paper questions.
  • Days 6-8: Quantitative Aptitude Test Consolidation: Practice applied concepts, terminology, analytical structures, and domain-specific problem sets.
  • Days 9-11: English Language Comprehension & Complementary Modules: Revise essential facts, regulatory rules, and cross-functional aptitude topics.
  • Days 12-13: Error Log & Viva Voce Preparation: Review weak topic areas and rehearse oral responses for the Departmental Selection Board interview.
  • Day 14: Full-Length Timed Mock Simulation: Complete two 100-MCQ timed mock tests strictly within 90 minutes to lock in pacing.

✅ 5. Examination Day Protocol & Merit Optimization Strategy

Candidates appearing for the ELECTRICAL SUPERVISOR (BS-16) (BS-16) screening examination should strictly observe official test center protocols: carry the original CNIC, printed Roll Number Slip, and black or blue ballpoint pens for OMR bubble shading. Allocate the first 45 minutes to high-confidence questions in Practical Electrical & Power Systems and Quantitative Aptitude Test before attempting multi-step analytical items. Maintain a minimum 80% accuracy rate across attempted items to absorb any negative marking deductions and secure a top-decile merit ranking for the Departmental Selection Committee interview.

Q. 1 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q1: In practical electrical wiring (Single & 3-Phase Wiring Standards), what is the installation rule for standard single-phase wiring u?
A
Standard single-phase wiring uses Brown for Live, Blue for Neutral, and Green/Yellow for Earth (IEC 60446).
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Standard single-phase wiring uses Brown for Live, Blue for Neutral, and Green/Yellow for Earth (IEC 60446).
Q. 2 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q2: How is balanced 3-phase systems feature th correctly implemented in residential/industrial installations (Single & 3-Phase Wiring Standards)?
A
Balanced 3-phase systems feature three line voltages displaced by 120 degrees electrical.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Balanced 3-phase systems feature three line voltages displaced by 120 degrees electrical.
Q. 3 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q3: Under electrical wiring code (Single & 3-Phase Wiring Standards), which standard specifies staircase lighting uses two 2-wa?
A
Staircase lighting uses two 2-way SPDT switches connected via two traveler strapping wires.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Staircase lighting uses two 2-way SPDT switches connected via two traveler strapping wires.
Q. 4 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q4: In building electrical installations (Single & 3-Phase Wiring Standards), what requirement governs controlling lights from 3+ loc?
A
Controlling lights from 3+ locations requires Intermediate (4-terminal crossover) switches between 2-way switches.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Controlling lights from 3+ locations requires Intermediate (4-terminal crossover) switches between 2-way switches.
Q. 5 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q5: How does an electrician wire and troubleshoot ring main socket circuits lo in Single & 3-Phase Wiring Standards?
A
Ring main socket circuits loop from and return to the DB, providing two parallel current paths.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Ring main socket circuits loop from and return to the DB, providing two parallel current paths.
Q. 6 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q6: Under 3-phase and single-phase wiring regulations (Single & 3-Phase Wiring Standards), what rule dictates loop-in lighting wiring makes all?
A
Loop-in lighting wiring makes all cable joints accessible inside switches or ceiling roses.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Loop-in lighting wiring makes all cable joints accessible inside switches or ceiling roses.
Q. 7 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q7: In motor control and branch circuit wiring (Single & 3-Phase Wiring Standards), which standard applies to heavy thermal appliances (ac, g?
A
Heavy thermal appliances (AC, geysers) require dedicated 15A/16A power sockets with 4.0 mm² cables.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Heavy thermal appliances (AC, geysers) require dedicated 15A/16A power sockets with 4.0 mm² cables.
Q. 8 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q8: What is the safety and operational purpose of single-pole light control swi in Single & 3-Phase Wiring Standards?
A
Single-pole light control switches must ALWAYS be connected in series with the Live (Phase) wire.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Single-pole light control switches must ALWAYS be connected in series with the Live (Phase) wire.
Q. 9 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q9: In practical electrical wiring (Single & 3-Phase Wiring Standards), what is the installation rule for maximum allowable voltage drop?
A
Maximum allowable voltage drop is 3% for lighting circuits and 5% for power socket circuits.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Maximum allowable voltage drop is 3% for lighting circuits and 5% for power socket circuits.
Q. 10 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q10: How is conduit space fill factor must not correctly implemented in residential/industrial installations (Single & 3-Phase Wiring Standards)?
A
Conduit space fill factor must not exceed 40% to allow heat dissipation and easy cable pulling.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Single & 3-Phase Wiring Standards: Conduit space fill factor must not exceed 40% to allow heat dissipation and easy cable pulling.
Q. 11 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q11: In practical electrical wiring (Industrial Motor Control & Wiring), what is the installation rule for power factor correction capaci?
A
Power factor correction capacitor banks connect in parallel to supply leading kVAR to inductive motor loads.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Power factor correction capacitor banks connect in parallel to supply leading kVAR to inductive motor loads.
Q. 12 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q12: How is flexible cords must match appliance correctly implemented in residential/industrial installations (Industrial Motor Control & Wiring)?
A
Flexible cords must match appliance ampacity: 0.75 mm² (6A), 1.5 mm² (16A), and 2.5 mm² (25A).
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Flexible cords must match appliance ampacity: 0.75 mm² (6A), 1.5 mm² (16A), and 2.5 mm² (25A).
Q. 13 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q13: Under electrical wiring code (Industrial Motor Control & Wiring), which standard specifies industrial perforated metal cabl?
A
Industrial perforated metal cable trays must be continuously bonded to the Main Earthing Terminal.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Industrial perforated metal cable trays must be continuously bonded to the Main Earthing Terminal.
Q. 14 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q14: In building electrical installations (Industrial Motor Control & Wiring), what requirement governs star-delta starters reduce mot?
A
Star-Delta starters reduce motor starting inrush current to 1/3 by starting in Star before switching to Delta.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Star-Delta starters reduce motor starting inrush current to 1/3 by starting in Star before switching to Delta.
Q. 15 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q15: How does an electrician wire and troubleshoot direct-on-line (dol) starter in Industrial Motor Control & Wiring?
A
Direct-On-Line (DOL) starters connect motors across full line voltage with a contactor and thermal overload relay.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Direct-On-Line (DOL) starters connect motors across full line voltage with a contactor and thermal overload relay.
Q. 16 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q16: Under 3-phase and single-phase wiring regulations (Industrial Motor Control & Wiring), what rule dictates single-phasing occurs when one su?
A
Single-phasing occurs when one supply line opens, drawing excessive current on remaining lines and burning windings.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Single-phasing occurs when one supply line opens, drawing excessive current on remaining lines and burning windings.
Q. 17 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q17: In motor control and branch circuit wiring (Industrial Motor Control & Wiring), which standard applies to ceiling fan speed regulators us?
A
Ceiling fan speed regulators use non-dissipative capacitors or triac circuits to vary motor terminal voltage.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Ceiling fan speed regulators use non-dissipative capacitors or triac circuits to vary motor terminal voltage.
Q. 18 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q18: What is the safety and operational purpose of normally open (green) buttons in Industrial Motor Control & Wiring?
A
Normally Open (Green) buttons start contactors with 13-14 seal-in contacts; Normally Closed (Red) buttons stop circuits.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Normally Open (Green) buttons start contactors with 13-14 seal-in contacts; Normally Closed (Red) buttons stop circuits.
Q. 19 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q19: In practical electrical wiring (Industrial Motor Control & Wiring), what is the installation rule for photocells (cds ldrs) automati?
A
Photocells (CdS LDRs) automatically switch street lights ON at dusk and OFF at dawn with built-in time delay.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Photocells (CdS LDRs) automatically switch street lights ON at dusk and OFF at dawn with built-in time delay.
Q. 20 Practical Electrical & Power Systems
Difficulty: Medium (1 Mark)
Q20: How is concealed pvc conduit embedded in b correctly implemented in residential/industrial installations (Industrial Motor Control & Wiring)?
A
Concealed PVC conduit embedded in brickwork provides superior mechanical isolation and fire resistance.
✓ Correct
B
Directly shorting live phase conductors to earth ground
C
Using flammable paper insulation inside distribution conduits
D
Connecting single-pole switches on the neutral line
💡 Step-by-Step Explanation & Concept Rationale
Under Industrial Motor Control & Wiring: Concealed PVC conduit embedded in brickwork provides superior mechanical isolation and fire resistance.
Q. 21 Practical Electrical & Power Systems
Difficulty: Easy (1 Mark)
Q21: In electrical installation practice #21, what is the purpose of a 'Ceiling Rose'?
A
To provide a secure, standardized connection point between fixed ceiling wiring and flexible pendant lamp cords
✓ Correct
B
To convert alternating current into 12V direct current
C
To act as a high-voltage lightning surge diverter
D
To amplify incoming line voltage
💡 Step-by-Step Explanation & Concept Rationale
A ceiling rose terminates fixed conduit wiring and connects flexible cords to light fittings.
Q. 22 Practical Electrical & Power Systems
Difficulty: Easy (1 Mark)
Q22: In electrical installation practice #22, what is the purpose of a 'Ceiling Rose'?
A
To provide a secure, standardized connection point between fixed ceiling wiring and flexible pendant lamp cords
✓ Correct
B
To convert alternating current into 12V direct current
C
To act as a high-voltage lightning surge diverter
D
To amplify incoming line voltage
💡 Step-by-Step Explanation & Concept Rationale
A ceiling rose terminates fixed conduit wiring and connects flexible cords to light fittings.
Q. 23 Practical Electrical & Power Systems
Difficulty: Easy (1 Mark)
Q23: In electrical installation practice #23, what is the purpose of a 'Ceiling Rose'?
A
To provide a secure, standardized connection point between fixed ceiling wiring and flexible pendant lamp cords
✓ Correct
B
To convert alternating current into 12V direct current
C
To act as a high-voltage lightning surge diverter
D
To amplify incoming line voltage
💡 Step-by-Step Explanation & Concept Rationale
A ceiling rose terminates fixed conduit wiring and connects flexible cords to light fittings.
Q. 24 Practical Electrical & Power Systems
Difficulty: Easy (1 Mark)
Q24: In electrical installation practice #24, what is the purpose of a 'Ceiling Rose'?
A
To provide a secure, standardized connection point between fixed ceiling wiring and flexible pendant lamp cords
✓ Correct
B
To convert alternating current into 12V direct current
C
To act as a high-voltage lightning surge diverter
D
To amplify incoming line voltage
💡 Step-by-Step Explanation & Concept Rationale
A ceiling rose terminates fixed conduit wiring and connects flexible cords to light fittings.
Q. 25 Practical Electrical & Power Systems
Difficulty: Easy (1 Mark)
Q25: In electrical installation practice #25, what is the purpose of a 'Ceiling Rose'?
A
To provide a secure, standardized connection point between fixed ceiling wiring and flexible pendant lamp cords
✓ Correct
B
To convert alternating current into 12V direct current
C
To act as a high-voltage lightning surge diverter
D
To amplify incoming line voltage
💡 Step-by-Step Explanation & Concept Rationale
A ceiling rose terminates fixed conduit wiring and connects flexible cords to light fittings.
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