The ballast unit component uv ac is to be used for the power regulation of uv-lamps up to 15 kw nominal power. Reliable ignition even of “bad starter“uv lamps. Operation of mercury medium pressure and metal halide lamps with electrical characteristics corresponding to the wide working range of the ballast unit. With or without half power switch. More power steps available on request. Mounted on ground plate for installation into uv curing machine.