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Humidity measurement – even under extreme conditions

Trace humidity measurement - testo 6615 High humidity measurement - testo 6614 Humidity measurement in the lowest humidity range is also verydemanding. If “normal” polymer humidity sensors are used here, the error, measured in dewpoint degrees, soon shows high values.For the demanding measurement of trace humidity, Testo hasdeveloped the testo 6615, which has an integrated trace humidity self-adjustment. The smallest discrepencies are corrected cyclically here, up to trace humidities of -60° dewpoint! Humidity measurement in the high humidity range is among the mostdifficult mesasurement tasks. Unstable measurement values, delayed signal reaction, and sometimes also sensor corrosion are no rarity, if a special solution is not usedFor these applications, Testo has developed a special, heatedhumidity sensor with the testo 6614. A microclimate which is 5 Kelvin above the process conditions is thus created inside the filter. The considerably lower humidity in the microclimate greatly improves the sensor reaction as well as noticeably reducing the likelihood of corrosion.Parallel to the heated humidity sensor, the testo 6614 also has anadditional temperature probe. This measures the actual process temperature; on this basis the correct process humidity is calculated in the microprocessor of the measurement transmitter, and displayed. Humidity measurement in corrosive media – testo 6617 Humidity measurement in corrosive media is often accompanied by ashort useful life of the sensor. For this problem too, Testo has developed a ground-breaking innovation: cover electrode monitoring.Thanks to this measure, the first signs of corrosion are detected andreported early. This early warning allows the measurement probe to be exchanged before the measurement is false or even interrupted. This guarantees optimum system availability!