Question 162Electricity & Electronics - QMED

70% to pass

Which of the following precautions should be taken when troubleshooting various power circuits using a digital multimeter?

ANever use this type of meter on circuits greater than 60 Hz as the meter may not register voltages over 60 Hz.
BNever connect the device to circuits where potentials greater than 120 volts may be present, as the internal electronics can only withstand small currents.
CAlways remember that the unit is polarity sensitive and if used on DC circuits reversing the leads may result in high temperatures within the tester.
DWhen in the manual ranging mode, always pre-set the meter to the next higher range than the amount of voltage expected in the circuit.
AI Explanation

The correct answer is D) When in the manual ranging mode, always pre-set the meter to the next higher range than the amount of voltage expected in the circuit. This is the correct answer because when using a digital multimeter in manual ranging mode, it is important to set the meter to the next higher range than the expected voltage in the circuit. This helps prevent damage to the meter's internal components from an unexpectedly high voltage. Using the wrong range can overload the meter and potentially cause it to malfunction or even be permanently damaged. The other options are incorrect. Option A is incorrect because digital multimeters are capable of measuring voltages up to several kilohertz. Option B is incorrect because modern digital multimeters are designed to withstand voltages up to several hundred volts. Option C is incorrect because digital multimeters are generally not polarity sensitive and reversing the leads will not result in high temperatures within the tester.

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