Which mechanism causes widespread voltage sag when an urban electrical substation’s main breaker trips?

💡 Explanation

Cascading thermal overload tripping by increased current draw and reactive power imbalance initiates a cycle of stress on adjacent breakers; therefore, the system collapses, rather than stabilizing, because each breaker is thermally limited.

• Which operational hazard increases when harmonic currents flow within three-phase power transformers due to non-linear loads?
• Which risk increases when microwave antennas experience heavy icing?
• Which outcome occurs when a three-phase power transformer in a distribution system experiences single-phase isolation?
• Which material fatigue risk increases within an engine's pistons during rapid deceleration?
• Which consequence results when an inadequately sized isolating circuit breaker interrupts a charging current in a large capacitor bank?
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