In the design and maintenance of cold storage systems, wire sizing might seem like a basic step, but it often becomes an invisible "killer" of equipment. To save effort or reduce costs, many technicians opt for wires with a smaller cross-sectional area, overlooking the significant technical risks hidden behind this practice.Taking a common 10 HP refrigeration unit as an example, the standard wire size corresponding to its rated current should be a 6 mm² copper core wire. 

           However, it's not uncommon to find 4 mm² wires used as substitutes on site. The root of the problem lies in the instantaneous current surge during startup, which can be 3 to 5 times the rated current. If the wire cross-section is insufficient, the line impedance increases, leading to a significant voltage drop and aggravated current overload during startup.Long-term operation under critical load causes continuous heating of the wires, accelerating the aging of the insulation layer and easily triggering the overload protector to trip. More seriously, the main contactor, subjected to frequent high-current surges, experiences intensified contact arcing, coil overheating, and increased contact resistance, creating a vicious cycle. In minor cases, 

         The equipment frequently shuts down for protection, affecting the temperature stability of the cold room. In severe cases, the contactor burns out, potentially leading to line short circuits or fire hazards.Wire sizing is not an "approximate" engineering task; it is the first line of defense ensuring the stable operation of the unit. Every correct choice is a valuable investment in equipment lifespan and operational safety. Don't let a single wire become the weak link in your entire refrigeration system.