The outlet end of the power cord of the light box is on the back. If the power cord is on the back of the light box, you can cut off the plug of the power cord and connect it directly, and tie the power connector tightly with insulating tape. If the power cord is outside the location where the light box is installed, you can connect the outlet of the light box power cord to the edge of the light box, and then plug it into the power socket with a three-phase plug.
Aim at the fixed point (that is, drill a hole in the power cord position of the light box base with an electric drill, reinstall the power cord, adjust it to a horizontal state with a level meter, turn on the light and clean the surface of the light box.