DE2829665

The high-temperature reference electrode (10) is used in a measuring device for determining the oxygen content of water at very high temperature. At one end it has a sealed tube (12), preferably made of a palladium-silver alloy. The latter is pressurised with hydrogen from a feed line (18) and is loosely enclosed in a perforated sleeve (14). Through openings (16) in the sleeve, water enters the narrow gap between the tube (12) and the sleeve (14), is retained in the gap and is saturated with hydrogen, which diffuses through the wall of the tube (12). This provides a constant value which serves as a reference level for the measurements of oxygen content carried out together with a measuring electrode. The reference electrode is used in boiler construction, mainly in nuclear reactor boilers.