What does a zero reading indicate on an ohmmeter?

A zero reading on an ohmmeter indicates that the circuit is closed with no resistance. This means that the two points across which the measurement is being taken are effectively connected with a conductor that has negligible resistance, allowing electrical current to flow freely. In practical terms, it suggests that the connections are complete, and the component or conductor being tested is functioning properly without any interruptions.

When measuring resistance, ohmmeters supply a small voltage and measure how much current flows. A zero reading occurs when the measured resistance is so low that it falls within the meter's capability to detect the minimal resistance, indicating a good electrical connection.

In context, this differs from what would be represented by an open circuit (which would show infinite resistance), a short circuit (which would imply very low resistance but not necessarily a zero reading depending on the circuit design), or a requirement for calibration (which would not accurately reflect the circuit status at all). Understanding these distinctions is vital for anyone working with electrical measurement, as it directly relates to troubleshooting and confirming circuit integrity.