Digital psychrometer, FPAD 36-3 with ALMEMO® D6 plug with integrated atmospheric pressure sensor, for automatic pressure compensation • Digital temperature sensors (adjusted) with high precision and synchronism up to 90 °C. • Automatic air pressure compensation with built-in air pressure sensor. • Stable sensor cable. • Version optimized for long-term measuring operations • Automatic humidification of the wick after filling the water tank. General features of ALMEMO® D6 sensors: see chapter ALMEMO® Measuring instruments 11/2025 • We reserve the right to make technical changes. Technical data and functions • The two digital Pt100 sensors for dry temperature and wet temperature are characterized by particularly high precision and synchronism up to 90 °C. The Pt100 sensors are connected to the digital ALMEMO® D6 connector (as a complete measuring chain) adjusted at 0 °C, 25 °C, 85 °C in the calibration laboratory. The accuracy of the temperature measurement is thus independent of the ALMEMO® measuring instrument. The two digital Pt100 sensors are easily exchangeable in case of service. • Stable sensor cable with shielding and insulation FEP. • The digital psychrometer can be operated with any ALMEMO® measuring instrument without affecting its measuring accuracy. The digital psychrometer is calibrated without ALMEMO® device. • A digital atmospheric pressure sensor integrated in the ALMEMO® D6 plug itself provides automatic pressure compensation for all pressure-dependent humidity variables. • Humidity calculation (Calculation is done in the ALMEMO® D6 connector) on the basis of formulae as per Dr. Sonntag and the enhancement factor as per W. Bogel (correction factor fw(t,p) for real mixed gas systems) This substantially widens the measuring range and improves the accuracy of humidity variable calculations. • Humidity variable Absolute humidity in g/m3 • Temperatures are measured using A/D converter incorporated in the ALMEMO® D6 plug. • The humidity variables are calculated from the three primary measuring channels (real measurable variables): Dry temperature, wet temperature, atmospheric pressure • Freely selectable measurable variables Four measuring channels are programmed (at our factory): dry temperature (°C, TT, t), wet temperature (°C, HT, tw), relative humidity (%H, RH, Uw), atmospheric pressure (mbar, AP, p) Other humidity variables can also be selected: dewpoint (°C, DT, td), mixture (g/kg, MH, r), absolute humidity (g/m3, AH, dv), vapor pressure (mbar, VP, e), enthalpy (kJ/kg, En, h) This device can be configured directly on a PC using USB adapter cable ZA 1919 AKUV (see chapter „Networking“). Recommendations for calibration laboratories and quality assurance Reference measuring instrument ALMEMO® 1036-2 is ideally suited for use in calibration laboratories and quality assurance procedures. When measuring atmospheric humidity the combination of reference measuring instrument ALMEMO® 1036-2 and precision psychrometer FPA-836-3P3 ensures very high levels of resolution, precision, and linearity. Resolution parameters: temperature Pt100 0.001 K, relative humidity 0.01 %, dewpoint 0.01 K The measuring instrument incorporates a digital atmospheric pressure sensor for compensation purposes. These devices are offered in a set including the sensor and a DAkkS accredited calibration certificate: Calibration points temperature/humidity at 25 °C / 30 % r.h. and 25 °C / 75 % r.h. and air pressure in the range 700 ... 1100 mbar. For general description and technical data see Chapter „ALMEMO® reference measuring instruments“.

Air humidity Digital stationary psychrometer FPAD 36-3 Technical data Operating temperature 0...+90 °C (no ice formation) Humidity measuring range 10 to 100 % RH Measuring system psychrometric at 10 to 90 °C and 900 to 1050 mbar Temperature sensors 2 x Pt100 class B Accuracy ALMEMO® adjusted Ventilator power supply 12 VDC via mains unit, cable approx. 1.5 meters and extension cable 5 m (included in delivery) Housing Plastic PMMA ALMEMO® connecting cable 2 Cables, FEP / Wire Shielding, 5 meters to 1 ALMEMO® D6 plug Digital atmospheric pressure sensor (integrated in ALMEMO® D6 plug) Measuring range...