FIELD: experimental, including reactor, investigations of thermionic converters and thermionic electricity-generating assemblies. SUBSTANCE: for early detection of leakage in device separating cesium system of test facility from evacuating system, neutral gas is fed to cesium system on vacuum-system side upon each open-close cycle of sealing device and leakage through sealing device is recognized by short-time temperature rise on external can of thermionic assembly. Helium, nitrogen, or mixture of these and other gases may be used as neutral gas. Gas is supplied at pressure o 130 to 1000 GPa. EFFECT: improved reliability of inspection results. 3 cl, 2 dwg
