Device and procedure for automatic determination of sediment height in a sediment meter

摘要

The appts. includes a fluorescent light source (6) connected to a fibre optic cable (7) and whose light is detected by a twin photodetector (5). Light from the source passes through an iris (8) and a diffusor (9) to a rod lens (10) via the cable. From the lens it is directed through a sediment collector tube (3) to the photodetector. The fibre bundle converts the beam cross-section from, e.g. a circle at the diffusor into an array of narrow vertical strips. Two lenses (11,12) concentrate the light from different levels on to photosensitive elements (13,14) of equal attenuation. The lower lens (12) tracks the level of sediment under the control of a servomotor (18).