Question 170Electricity & Electronics - QMED

70% to pass

When working on electrical circuits containing large capacitors, in addition to de-energizing the circuit, which of the listed precautions should also be taken?

AMeasure capacitor insulation resistance.
BKeep all radio equipment away.
CCheck capacitor circuit polarity.
DDischarge the capacitor through a 50,000 ohm resistor.
AI Explanation

The correct answer is D) Discharge the capacitor through a 50,000 ohm resistor. When working with large capacitors, simply de-energizing the circuit is not enough. Capacitors can retain a dangerous electrical charge even after the power source is removed. To safely discharge the capacitor, it should be connected to a high-value resistor, typically around 50,000 ohms, to allow the charge to bleed off gradually. This precaution is essential to prevent accidental shock or damage when handling the equipment. The other options, while potentially useful, do not directly address the hazard of the residual capacitor charge.

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