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Switchgear and Protection important questionsMost repeated in SPPU papers

These 31 questions appeared in more than one SPPU Switchgear and Protection paper we have: 9 papers, from Feb 2023 to Nov 2025. The most-asked come first. Each one links to the papers it was asked in.

All Switchgear and Protection papers and notes

Repeated questions

Endsem questions (25)

  1. 6×asked

    Explain the effect of Arc resistance on i) Impedance relay ii) MHO relay

    Nov 2025 ·May 2025 ·Nov 2024 ·May 2024 ·Nov 2023 ·May 2023

  2. 5×asked

    A Vacuum circuit breaker is rated as 3 phase,1600 A, 2000 MVA, 33 KV, 1 second. Determine i) Beaking current ii) Making current iii) STC iv) Rated normal current 2

    Nov 2025 ·May 2025 ·May 2024 ·Nov 2023 ·May 2023

  3. 4×asked

    Explain the following ratings of the circuit breaker. i) Making Capacity ii) Symmetrical Breaking capacity

    Nov 2025 ·May 2025 ·Nov 2024 ·May 2024

  4. 4×asked

    With neat diagram explain three stepped distance protection scheme.

    Nov 2025 ·Nov 2024 ·May 2024 ·May 2023

  5. 3×asked

    A 22 KV, 600MVA, 5 sec circuit breaker suddenly closes on occurring of fault. Determine i) The symmetrical breaking current ii) The asymmetrical breaking current assuming 50% DC component iii) The short time current rating iv) The peak making current

    Nov 2025 ·May 2025 ·Nov 2024

  6. 3×asked

    Explain Numerical Relay with its block diagram and state its application.

    Nov 2025 ·May 2025 ·Nov 2024

  7. 3×asked

    State advantages and disadvantages of static relay.

    Nov 2024 ·May 2024 ·Nov 2023

  8. 2×asked

    Discuss three demerits of Static Relay.

    Nov 2025 ·May 2025

  9. 2×asked

    Draw block diagram of Static Relay.

    Nov 2025 ·May 2025

  10. 2×asked

    Explain the Vacuum Circuit breaker with a neat diagram.

    Nov 2025 ·May 2025

  11. 2×asked

    Explain with a neat diagram puffer type SF6 circuit breaker.

    Nov 2025 ·May 2023

  12. 2×asked

    State abnormal conditions occurring in the Induction motor.

    Nov 2025 ·May 2025

  13. 2×asked

    State advantages and disadvantages of PLCC. ♣♣♣

    Nov 2025 ·May 2025

  14. 2×asked

    What do you mean by term Directional and Non - Directional overcurrent relay.

    Nov 2025 ·Nov 2024

  15. 2×asked

    Draw flowchart of Numerical algorithm.

    May 2025 ·Nov 2024

  16. 2×asked

    Explain current differential Relay.

    May 2025 ·Mar 2024

  17. 2×asked

    With neat diagram explain Air-Blast circuit breaker.

    May 2025 ·Nov 2024

  18. 2×asked

    Write a short note on Wide Area Measurement (WAM) System.

    May 2025 ·Nov 2023

  19. 2×asked

    Draw block diagram of PLCC scheme used for transmission line protection and briefly explain its components.

    Nov 2024 ·Nov 2023

  20. 2×asked

    Draw & explain the protection of 3 phase alternators against inter turn faults on same phase.

    May 2024 ·Nov 2023

  21. 2×asked

    Draw neat diagram and explain the construction and working principle of vacuum circuit breaker?

    May 2024 ·May 2023

  22. 2×asked

    State and explain the sampling theorem. Explain use of anti - aliasing filter in numerical relay.

    May 2024 ·Nov 2023

  23. 2×asked

    What is Auto Reclosing? Discuss single shot and multi shot auto reclosing of circuit breakers.

    May 2024 ·May 2023

  24. 2×asked

    With neat block diagram explain working of Numerical relay. Also state its advantages over static & conventional relay.

    May 2024 ·Nov 2023

  25. 2×asked

    A three phase 11 kV/ 132 kV, delta / star connected power transformer is protected by percentage differential protection scheme. The CTs on LT side have ratio of 600/5. Determine the CT ratio on HT side.

    Nov 2023 ·May 2023

Insem questions (6)

  1. 2×asked

    A 3phase, 50Hz, alternator has inductance of 3 mH/ph and capacitance of 0.025 microfarad/ph, the circuit breaker opens when RMS current is of 8000 Amp. Analyse and Determine. i) Frequency of oscillation ii) Peak restriking voltage iii) Maximum value of RRRV

    Mar 2025 ·Mar 2024

  2. 2×asked

    Derive the torque equation of induction type relay.

    Mar 2025 ·Feb 2023

  3. 2×asked

    What is Relay? Explain trip circuit of circuit breaker with neat diagram.

    Mar 2025 ·Feb 2023

  4. 2×asked

    Explain different causes of faults in a power system.

    Mar 2024 ·Feb 2023

  5. 2×asked

    Explain high and low resistance principles of arc interruption in case of circuit breakers?

    Mar 2024 ·Feb 2023

  6. 2×asked

    With a suitable diagram explain construction & working of Induction disc type overcurrent relay?

    Mar 2024 ·Feb 2023

Questions count as repeated when their wording matches closely across papers. Numericals that depend on a figure are left out, since the figure changes from paper to paper.