1. A welder's trainer comprising: a welding situation simulation unit having an input and made in the form of a TV-type display having a screen: a welding electrode simulator having an input and an output; a welding process heat balance electronic model having an input and an output; a welding situation visual synthesis electronic model having inputs and a first and second outputs; said first output of said visual synthesis electronic model connected to said display; a training control and monitoring unit having first, second and third inputs and a first output, said first output connected to said input of said welding electrode simulator, a second output connected to said input of said heat balance electronic model and a third output connected to said input of said visual synthesis electronic model, said first input connected to the output of the welding electrode simulator, said second input connected to the output of the heat balance electronic model and said third input connected to the second output of the visual synthesis electronic model, in which said welding situation simulation unit is connected to said visual synthesis electronic model that provides an electronic model for visual synthesis of the welding situation on the display screen that is part of said welding situation simulation unit; the welding situation simulation unit is connected to the trainer monitoring and control unit through the visual synthesis electronic model.