Sight gauge installation for the remote sensing of a liquid-level.

摘要

This invention provides a liquid level sight gauge installation comprising at least one liquid level video gauge having an upwardly extending sight tube (10) which at or near its lower end is in fluid flow communication with the content of a tank (11) for holding liquid, a scale (15) extending substantially parallel with said sight tube (10), a video camera (20) for viewing the sight tube (10) and scale (15) and means (56) for moving the camera along the sight tube and scale. A monitor (40) is provided having a screen (41) for displaying the view of the sight tube (10) and scale (15) afforded by the camera (20), there being means (51) provided for generating and displaying on the monitor screen (41) a cursor line (55) which extends generally horizontally across the view of the sight tube (10) and scale (15) displayed on the monitor screen (41). Means (X and Y of 51) are provided for moving that cursor line (55) upwardly and downwardly of the monitor screen (41) through an adjustment zone whose height is of predetermined extent (Z), all so that the cursor line (55) can be adjusted to appear at a desired position in relation to the view displayed on the screen (41).