Protect zero circuit

The protective zero connection is a technical measure to connect the metal casing of electrical equipment such as motors and household appliances to the neutral line of the 380V three-phase four-wire power supply system
through wires. Its function is to prevent electrical leakage once the insulation of electrical equipment is damaged. Leakage current can cause the protection device to operate or the melt to fuse,
thereby automatically cutting off the power supply, as shown in Figure 14-2. It is worth noting that in the same power grid, the same protection method should be used, and some
electrical to be connected. zero, while other electrical equipment is grounded.