FIELD: nuclear power plants; metering boron concentration in coolant circuits. SUBSTANCE: metering device has mobile transmitter and mobile receiver with intermediate connection of at least one spatial area being cooled to place cooling circuit on coolant- carrying component. Spatial area has cooling channel with cooling medium flowing over it. Cooling medium used for the purpose is air. Transmitter and receiver are mounted in respective chambers. Transmitter is essentially neutron source and receiver, charged-particles counter. Device is provided with temperature and tension-resistant facilities. Device is made so that metering path length between transmitter and receiver is maintained constant irrespective of variations in environmental conditions. EFFECT: provision for boron concentration measurements without intervention in cooling circuit; facilitated procedure. 16 cl, 2 dwg
