A system and method for installing device drivers or application software on equipment used in brazing, cladding, building up, filling, hard-facing overlaying, joining or welding operations is provided. In order to avoid the tap becoming jammed in the open position, said means limiting the movement of the operating member consist of an abutment and a counterabutment with frontal contact, which are arranged respectively on a rotary element and on the body of the tap, or vice versa. A retention mechanism retains the front cover at the closed position.