When welding rods are electrical arc welded, the current values with a maximum load voltage contains a maximum load voltage, which makes electric arc unlikely to be extinguished when point welding is in the process. For these factors, the invention provides an electric arc welder comprising a direct-current power circuit rectified and smoothed from a commercially used alternating current power source to output direct voltages; the direct voltages undergo a voltage changing process into an invert circuit with high frequency alternating voltages, which also undergo a voltage changing process into a main voltage transformer providing alternating current voltages applicable to welding; the voltages outputted from the main transformer is rectified as a secondary rectifying circuit; a detection circuit detecting the outputted current after the rectification and a main control circuit controlling the invert circuit based on the detection of the outputted current are also provided hereby in the invention. With the introduction of a point welding mould to decide a circuit, the main control circuit functions to reduce the maximum load of various outputted current so that the external performances of the electric characteristics can be controlled.