A grounding socket is a socket with a grounding wire, which is a commonly used three-hole socket. The hole on the three-hole socket is a grounding wire, with a neutral wire (N) on the left and a live wire (L) on the right. Generally, single-phase electrical equipment, especially mobile electrical equipment, should use three-core plugs and matching three-hole sockets.
There is a dedicated protective zero (ground) jack on the ground socket. When using zero protection, some people often only connect the post of this hole in the bottom of the socket to the neutral wire introduced into the socket. Direct connection is extremely dangerous. Because if the neutral wire of the power supply is disconnected, or the live (phase) wire and neutral wire of the power supply are connected reversely, the metal parts such as the casing will also have the same voltage as the power supply, which will cause electric shock. Therefore, the dedicated grounding jack should be connected to the dedicated protective ground wire when wiring.