Question 86Electricity & Electronics - QMED

70% to pass

When troubleshooting electronic equipment, why should you use a high impedance multimeter?

Afor AC measurements only and a low resistance meter for DC measurements
Bwhenever a low impedance meter is not available, regardless of the components being tested
Cto prevent excess current flow through the meter that would damage it
Dso as not to load down the circuit and obtain erroneous voltage readings
AI Explanation

The correct answer is D) so as not to load down the circuit and obtain erroneous voltage readings. When troubleshooting electronic equipment, a high impedance multimeter is recommended to prevent loading down the circuit under test. A low impedance meter would draw excessive current from the circuit, potentially altering the voltage being measured and providing an inaccurate reading. By using a high impedance meter, the current drawn is minimized, allowing for a more precise voltage measurement without significantly affecting the circuit's operation. This is important to obtain reliable diagnostic information when troubleshooting electronic components and systems. The other options are incorrect because: A) A high impedance meter is recommended for both AC and DC measurements, not just AC. B) Using a high impedance meter is the preferred practice, not just when a low resistance meter is unavailable. C) Preventing damage to the meter is a secondary consideration, the primary reason is to avoid loading down the circuit.

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