Measuring appliance for a nuclear reactor

This measuring appliance permits simultaneous measurement of neutron or gamma flux and temperature at the same position. As sensor there is used a tube-shaped conductor with a coaxial platinum wise in a filling mass of Al2O3. From about 4.3 m of such a coaxial cable a rodshaped sensing head with a length of 175 mm is obtained. The winding, having got an outer diameter of 6 mm, is - directly or by interconnecting a ceramic insulating collar - enclosed by a metallic protective cartridge. By means of ceramic stoppers the measurign points in the sensing head are transferred to a transmission line and connected with an electronic amplifying assembly. In order to permit the elimination of interferences in the transmission line and in the amplifying circuits on evaluating the temperature signal by means of a cross-correlation circuit the latter points are connected with 4 wires. Finally a wire without connection in the sensing head is running along the transmission cable. (HP)