The PM 400N power source is primarily used for welding structural steels in heavy engineering, metal structure manufacturing, container and tank manufacturing, transportation engineering, and more. It handles work perfectly under the harsh conditions of modern manufacturing. It can withstand 100% workload, high dust content, vibration, and significant power supply drops. Stable wire feed speed is ensured by the use of optical sensors and high-speed feedback between the power source and the wire feed mechanism. The arc length control function helps achieve uniform weld formation and penetration depth.