What should you check before connecting a voltmeter to a circuit?

Before connecting a voltmeter to a circuit, it is essential to check the measurement range setting on the voltmeter. This is crucial because voltmeters typically have various settings that correspond to different voltage levels. If the setting is too low for the voltage in the circuit, it could result in damage to the voltmeter or provide an inaccurate reading. Conversely, if the setting is too high, the voltmeter may not utilize its full scale, leading to a lack of resolution in the measurement. Hence, ensuring that the measurement range matches or exceeds the expected voltage ensures accurate and safe operation.

The other aspects, while important in general circuit handling, do not directly pertain to the immediate task of using a voltmeter. Checking wire color coding or the circuit's integrity may affect safety and proper operation but do not influence the voltmeter's functionality as directly as the correct range setting does. Similarly, verifying the power source voltage rating is relevant for overall circuit safety but does not specifically impact the voltmeter connection process.