초록 ▼

In a fluid level measurement system for the measurement of a level of fluid in a vessel the electrical impedance of a first conduction path between a central rod electrode and a surrounding cylindrical electrode and the electrical impedance of the second conduction path between the cylinder and the

In a fluid level measurement system for the measurement of a level of fluid in a vessel the electrical impedance of a first conduction path between a central rod electrode and a surrounding cylindrical electrode and the electrical impedance of the second conduction path between the cylinder and the vessel are established. The first conduction path is restricted to be below the minimum fluid level by an insulating coating on the rod. The second conduction path varies with the fluid level. An output signal is extracted from the electrodes potentiometrically which is indicative of the fluid level. The signal may be linearized by application to a circuit having a matched non-linear transfer function. With this arrangement, a continuous output signal indicative of the fluid level is produced which is not subject to errors due to changes in fluid resistivity.

대표청구항 ▼

A fluid level measurement system for measuring the level of a fluid in a vessel over a range of interest between two selected limiting points and above a minimum level of said fluid comprising: a first pair of electrodes for establishing a first conduction path through the fluid, each of the electro

A fluid level measurement system for measuring the level of a fluid in a vessel over a range of interest between two selected limiting points and above a minimum level of said fluid comprising: a first pair of electrodes for establishing a first conduction path through the fluid, each of the electrodes of said first pair being selectively insulated from fluid over a portion of each of said electrodes, with one of said electrodes being insulated from fluid over said range of interest such that said first path is completely below said minimum level, said first conduction path having a first impedance; a second pair of electrodes for establishing a second conduction path through the fluid, said second path varying with fluid level over said range of interest and having a second variable impedance; wherein said vessel is conductive and acts as one of said electrodes; energy supply means for establishing conduction through both said first and said second conduction paths; means for deriving an electrical output signal dependent upon the impedance ratio of said first path and said second path; and means for generating from said electrical output signal an output representative of fluid level.