The location and number of switches and sockets should be carefully considered when wiring. The height of the switch or socket in the same room must be the same. Generally, the switch is 1.4 meters from the floor and the outlet is 0.3 meters from the floor. The switch between the door and the guesthouse should be installed when the owner comes home, and the door can be easily occupied. The number of sockets in the room should not be too small. If the number of outlets is too low, the user only suffers from unwieldy wires and plugs the socket board, causing unsafe hidden troubles. Therefore, the number of sockets must be considered ahead of time, even if the use of the terminal board is reduced. In general, two sockets should be set up in the interior of a room, and the number of sockets in a two-compartment room should not be less than one or four.