Experimental validation of new method of temperature compensation for MI type continuous level probe in sodium

Mutual inductance (MI) type continuous level probe working, on the principle of variation of mutual inductance between two windings when they are immersed in an electrically conducting fluid such as sodium, is used in primary and secondary sodium systems of Prototype Fast Breeder Reactor (PFBR), for monitoring sodium level in sodium tanks and vessels. When the sodium level increases, the secondary voltage reduces. This reduction in voltage is a measure of sodium level. For a given level, as the temperature of sodium increases, the level reading decreases. As the operating temperature of the level probe is wider ranging from 150 deg C to 550 deg C, temperature compensation is required for accurate level indication. The current method of temperature compensation is partial, which attributes to an error of +/- 3%. This report gives the new method for temperature compensation for accurate measurement. (author)