For home appliances, although the power cord is only an accessory, it plays a vital role in the use of the home appliance. If the power cord is broken, the entire appliance cannot be used. Household power cords should adopt BVV2×2.5 and BVV2×1.5 type wires. BVV is the national standard code and is a copper sheathed wire. 2×2.5 and 2×1.5 represent 2-core 2.5 square millimeters and 2-core 1.5 square millimeters, respectively. In general, 2×2.5 is used as the main line and trunk line, and 2×1.5 is used as a single electrical branch line and switch line. Single-phase air-conditioning dedicated line uses BVV2 × 4, and a dedicated ground wire is also provided.