A METHOD AND APPARATUS FOR DETERMINING THE PROPORTION OF A FOREIGN SUBSTANCE IN A TEST YARN

摘要

The invention relates to a method and a device for determining proportions of solid matter in a test material. In order to provide a method and a device of the said type by means of which proportions of solid matter in a test material can be easily and reliably determined, even in the case of transparent matter or matter of a similar colour to the test material, the test material is exposed to an electric field and dielectric properties of the field with, the test material are determined. Two electrical quantities (6Cfl, 6Cf2 or U, cos) are determined from the dielectric properties and combined, resulting in a characteristic value which is independent of the mass of the test material. The characteristic value is compared with a previously determined characteristic value for the matter in question and the proportion of solid matter is determined therefrom. (fig 1)