Which safety precaution should be taken when using a voltmeter?

The key to safely using a voltmeter lies in ensuring that it is set to the correct voltage range before connecting it to a circuit. This precaution is essential because voltmeters are designed to operate within specific voltage limits. If the voltmeter is not set correctly and the voltage exceeds its rated capacity, it could be damaged, or worse, it could present a safety hazard, such as an electrical shock or fire.

In addition, using the appropriate voltage range allows for accurate measurements, as overloading the meter can result in erroneous readings. By properly setting the voltmeter according to the expected voltage level in the circuit, you help ensure both your safety and the instrument's longevity and functionality.