The level of some liquids stored in tanks can vary significantly with temperature. Conventional level systems can result in errors up to 10%.
By using a cylindrical float pressing against an Interface Model SMA Load Cell in a patented design, our customer eliminates this error and is able to accurately measure liquid depth.
Taking advantage of the Archimedes Principal, the downward gravitational force on the liquid (and vapors in LP Gases) causes an upward force on the buoyancy tube which are immersed in the liquid. The net effect is a change in the product "weight" (force) which is measured with the SMA, a miniature strain gage load cell.
In tanks, the force is energy, not movement, and the buoyancy tube does not rise and fall. The process is unaffected by changes in density caused by temperature swings, and unaffected by changes in barometric pressure (which affects pressure gauge technologies).