Application and development on embedded online monitoring system for resistance spot welding

During the process of steel resistance spot welding,there are a lot of information on welding quality in the variety of dynamic resistance.Using embedded system to online monitoring the resistance of spot welding can improve the understanding on welding quality.The online monitoring system was developed to monitor welding current,electrode pressure,voltage between electrodes and displacement of electrode synchronously.Analyzed the relationship between the variety of resistance and the welding nugget information in the dual-phase steel DP600 spot welding,and introduced the principle on using the voltage signal instead of dynamic resistance to analysis welding quality.On the embedded system the Dynamic Range Chart method was used to analysis the splash information in DP600 spot welding.