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Sarkari MCQs Government Exam Question Bank
Question no. 28085

What triggers short-circuit currents_______________?

Select your answer for: What triggers short-circuit currents_______________?
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Answer: E. any of these

Explanation

Short-circuit currents can be triggered by various faults, including single line-to-ground, line-to-line, double line-to-ground, and three-phase faults. Any physical bridging of conductors or breakdown of insulation establishes low-impedance paths that draw massive fault currents. Different fault types result in varying current magnitudes, but all severely disrupt normal power system operations. A short circuit occurs when electrical current bypasses the normal load impedance, flowing through an unintended low-resistance path. Symmetrical faults like three-phase faults affect all phases equally, whereas asymmetrical faults involve unbalanced phase conditions. Insulation failure caused by aging, moisture, lightning, or physical damage is the primary root cause of electrical short circuits.

Single phase to ground faults represent only one specific category and do not account for multi-phase short circuit events. Limiting the cause to phase-to-phase faults ignores common ground faults and symmetrical three-phase short circuit conditions. Options listing only specific subsets are incomplete because any of the mentioned electrical faults can trigger short-circuit currents.

Subject
Engineering
Category
Electrical Engineering
Topic
—
Difficulty
medium

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