What is required for an ohmmeter connection?

For an ohmmeter connection, it is essential that the circuit being tested is de-energized, meaning it should not be live. This ensures safety and accuracy during the measurement of resistance. If the circuit is live, the ohmmeter could potentially damage the meter or give erroneous readings due to the interference from the voltage present.

The ohmmeter works by sending a small current through the resistance of the component being measured and then calculating the resistance based on the voltage drop across its terminals. If connected to a live circuit, it may be unclear whether you're measuring the resistance of the component or the live voltage, complicating the analysis.

Thus, for safe and accurate measurements, an ohmmeter should be connected to a powered-off circuit. This ensures the ohmmeter can function properly, providing readings that are specific to the component's resistance without the influence of any other electrical potential present in a live circuit.