MAGNETIC SUBSTANCE CONCENTRATION MEASURING DEVICE AND MAGNETIC SUBSTANCE CONCENTRATION MEASURING METHOD

摘要

A device for measuring a concentration of magnetic material has exciting coils 11a and an output coil 11b which generates exciting voltage when alternating current flows through the exciting coils 11a. Measurement means 6 is provided to measure variation in phase difference between voltages of the exciting and output coils 11a and 11b, so that a concentration of magnetic material is measured with high accuracy from variation in phase difference when a test object is caused to approach the exciting coil 11a or/and the output coil 11b. A minute concentration of magnetic material in the fluid is continuously measured.