A welding stock storage rack made from wire mesh bent to form a pyramid has a trapezoidal cross section and planar, vertical ends. Program information of a plurality of program cells is displayed in a visible window. The power plane and ground plane grids possess a left-right mirror relation to one another and are displaced to place the rhomboid’s corners to avoid overlapping any of the grid lines. The image transmitting panel is placed in parallel to the first display. Virtual lines connecting terminal portions forming each second terminal portion group form a triangle. The auxiliary LED light source includes a second circuit board mounted on the chassis and a second LED mounted on the second circuit board.