When using a multimeter to measure resistance, the technician should:

When measuring resistance with a multimeter, it is essential to disconnect the circuit from the control equipment. This is because a multimeter applies a small voltage to the circuit to measure resistance, and if the circuit remains connected, it may affect the reading due to the presence of other parallel paths for current flow or because of the voltage present in the circuit.

By disconnecting the circuit, the technician ensures that the resistance measurement is accurate and reflects only the resistor's value being measured, without interference from other components in the circuit. This practice helps to avoid damage to the multimeter and ensures the safety of both the technician and the equipment.