Lenght measuring of a strip roller path

Piros light grid support the rough measuring of pipe lenght. They supply reproducible signals for beginning of the pipe and its end undependent from the pipe diameter. Occupation of the strip roller path is monitoring by inductive proximity switches beneath the conveyor belts.                                 
 

If a pipe is detected by the light grid, the light grid sets a counter to zero in the plant control. By means of a incremental rotary transmitter which accompanies the pipe exact length measuring to +/- 1mm is possible.