Abstract: The characteristic of CAN bus is introduced, the principle and hardware construction of resistance welding network control system are analyzed. The communication protocol for resistance welding is determined. The commun- ication software, control software and management software are designed. The experiment result of resistance spot welding shows the controller runs rapidly and stably, and can be stretched easily. The controller can realize on-line control and data management in resistance spot welding, and can be used to the intelligent integration of information net for welding unit manufacturing.

Key words: Network control system, CAN bus, Resistance spot welding