The power cord is an accessory for home appliances, but it plays a vital role in the use of home appliances. If the power cord is broken, the entire appliance cannot be used. Household power cords should be wired with BVV2 x 2.5 and BVV 2 x 1.5 models. BVV is the national standard code, which is a copper sheathed wire. 2×2.5 and 2×1.5 represent 2 cores of 2.5 square millimeters and 2 cores of 1.5 square millimeters, respectively. Under normal circumstances, 2 × 2.5 do the main line, the trunk line, 2 × 1.5 to do a single electrical branch line, switch line. The single-phase air-conditioning line uses BVV2 × 4, and is equipped with a dedicated ground wire.