① Lighting
The main purpose of lamps is lighting.
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So you must first determine the lighting needs of the wall lamp, whether it is used to provide overall lighting or local lighting, or to decorate and create an atmosphere.
Generally speaking, the power of wall lights used for overall lighting of a 30-square-meter room is usually between 20 and 30 watts. If it is used as auxiliary lighting, the power only needs to be selected between 2-10 watts and matched with other main lights.