To use a digital multimeter to test a neutral wire, we recommend the following steps: Set the multimeter to the highest voltage setting in the AC range. Next, hold the black test lead and connect it to the ground wire. Connecting the probe to a grounded appliance or an object. Identifying the neutral wire in an electrical box is necessary when installing modern devices like smart switches or dimmers, which require a continuous, low-voltage power source. At the same time, a ground wire, which is usually a plain copper wire or occasionally, one with green insulation, is also connected to the neutral bus bar.
