GB595475A - Improvements in means for measuring the electrical conductivity of liquids - Google Patents

Abstract

595,475. Liquid resistances. GENERAL ELECTRIC CO., Ltd., and FRANKLIN, R. J. May 30, 1945, No. 13567. [Class 37] A device of the immersion type for measuring the conductivity of liquids comprises a chamber provided with orifices for the entry of liquid and escape means for the exit of air displaced by the entering liquid so arranged that when the device is immersed in a liquid there is no trapping of air and the only current path is through the liquid within the chamber. A cylinder 10 of moulded insulating material has its upper end closed by an insulating end plate 11 -through which is sealed a tube 12 of insulating material forming a handle. In the lower end of the cylinder 10 is fixed a ring 13 of insulating material having in its upper surface an annular groove 14 containing graphite 15. The outer edge of the ring 13 is spaced from the cylinder 10 by spacers 16 to provide orifices through which liquid can enter the measuring chamber 18 constituted by the lower part of the cylinder 10. Liquid can also enter through the central aperture 19. A second ring 20 is similarly arranged so that liquid can pass both through its central aperture 21 and through orifices around its outer edge. The ring 20 has in its lower surface an annular groove 23 containing graphite 24. Terminals 25 make contact with the graphite electrodes 15, 24 and are connected to cables 27, 28 which pass out through the handle 12. When the device is immersed in liquid with its axis approximately vertical liquid rises in the measuring chamber 18 and the part of the cylinder 10 above it, displaced air escaping through the open end of the handle 12. The cross-section of the cylinder 10 and the distance between the electrodes 15, 24 is preferably chosen such that the measured conductivity is that of an inch cube or a simple multiple or submultiple thereof.