What hazard is a ground-fault circuit interrupter primarily intended to reduce?
Correct Answer
A) Electric shock from leakage current to ground
A GFCI trips on a small imbalance between outgoing and returning current to reduce shock risk from ground-fault leakage. Other choices describe noise, voltage regulation, or high-current faults handled by overcurrent devices.
Why This Is the Correct Answer
A GFCI trips on a small imbalance between outgoing and returning current to reduce shock risk from ground-fault leakage. Other choices describe noise, voltage regulation, or high-current faults handled by overcurrent devices.
Why the Other Options Are Wrong
Option B: Apply transformer core noise to the gFCI function condition
Transformer core noise is a sound/vibration issue; a GFCI monitors current imbalance related to shock risk.
Option C: Apply voltage drop on long feeders to the gFCI function condition
Voltage drop is a feeder/branch-circuit performance issue; a GFCI is not a voltage-regulation device.
Option D: Limit gFCI function to overheating from a bolted short circuit
A bolted short circuit is handled by overcurrent protection; a GFCI targets small leakage current that can shock a person.
Memory Technique
Keep GFCI function as a cause-to-effect card with Electric shock from leakage current to ground on the back.
Reference Hint
Open Mechanical and Electrical Systems for Construction Managers, 4th Ed., 2024; use by topic index - grounding / bonding / GFCI / coordination to confirm that A GFCI trips on a small imbalance between outgoing and returning current to reduce shock risk from ground-fault leakage.
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