Embodiments of the disclosure generally provide a method and apparatus for processing a substrate in a vacuum process chamber. The switching mechanism connects the first-dimension separation channel to one of the trap columns and connecting the analysis channel to the other of the trap columns, and also switches connections between the trap columns and the channels. The road marking system generates a guidance light which seemingly moves along with the flow of traffic by suitably switching on and off the light source in the road marking units. A second identification means is disposed on the device that contains information that is identical to that of the first identification means.