Data logger ALMEMO® 4390-2 ALMEMO® data logger Precision measuring instrument in fitted panel design. Comprehensive range of functions for all application areas Increased measuring accuracy, fast measuring rate, 1 measuring input, 2 limit value relays, integrated. Option with double analog output. 11/2025 • We reserve the right to make technical changes. Technical data and functions • Increased measuring accuracy and stability • Fast measuring rate, up to 50 measuring operations per second. With SD memory card, up to 100 mops, optional for 1 channel up to 400 mops • 1 ALMEMO® input socket, suitable for all ALMEMO® sensors or 6-contact clamp connector socket, also for 26 V and 20 mA • More than 65 standard measuring ranges • Support for ALMEMO® plugs with multi-point adjustment, special linearization, and special measuring ranges • Higher measuring quality thanks to electrical isolation between measuring inputs and device power supply (device ground) • Data logger with internal EEPROM, sufficient for 16,000 measured values, configurable as linear or ring memory • Memory connector with micro SD (accessory) • As standard 2 limit value relays can also be driven via interface Technical data Precision class AA (see general technical specifications) Measuring rate (100), 50, 10 and 2.5 mops Measuring inputs 1 ALMEMO® input socket, suitable for all ALMEMO® sensors or 6-contact screw connector with input for 26 V (integrated divider) or 20 mA (integrated shunt) Accuracy Divider / shunt ±0.1 % of measured value Channels 4 channels for double sensors and function channels Electrical isolation for analog sensors between measuring input and power supply (device ground) Sensor power supply 12 V / 0.1 A; 9 V / 0.15 A; 6 V / 0.2 A Outputs 2 ALMEMO® sockets, suitable for all output modules (analog / data / trigger / relay cables, memory, etc.) 2 limit value relays Mechanical changeover, 230 V, 2 A Option with double analog output 10 V or 20 mA (programmable) 16-bit DAC, electrically isolated • Option with double analog output can also be driven via interface • 2 ALMEMO® output sockets, suitable for digital interfaces, analog output, trigger input, alarm contacts, memory card • Programming functions displayed in normal text (3 languages) • 5 programming menus: Measuring function, memory, sensor, device, output • Measuring functions: Measured value, dual display, smoothing, zero-setting, setpoint adjustment, maximum / minimum / average values, temperature compensation, atmospheric pressure compensation • Sensor programming: Measuring range, measured value correction, scaling, units, limit value monitoring, graduated locking of functions, scaling of analog output • Device programming: Conversion rate, real-time clock with date, output cycle, baud rate, choice of languages 0.5 mV / digit, load >100 kilo ohms 0.1 mA / digit, load <500 ohms ±0.1 % of measured value ±0.1 % of final value 10 ppm / K 100 ps Standard equipment Keypad 5 membrane keys Date and time-of-day Real-time clock, buffered with battery Memory, internal EEPROM sufficient for 16,000 measured values Power supply Option U 10 to 30 V, 0.5 A, electrically isolated Housing Standard plastic housing 96 x 48 x 132 mm (WxHxD) Panel opening 90 x 42.5 mm Environmental conditions see general technical data Memory connector with micro SD, including USB card reader (see chapter „Output modules“) ZA1904SD Measuring rate 400 mops (SD card required) SA0000Q4 Power supply 10 to 30 VDC, electrically isolated OA4390U 2 analog outputs (common ground), electrically isolated 10 V or 20 mA (programmable) OA4390R02 Temperature ranges for 8 refrigerants SB0000R2 Standard delivery Order no. Operating instructions, manufacturers test certificate, Precision measuring instrument ALMEMO® 4390-2 MA43902 DAkkS accredited calibration or works calibration KE90xx, electrical, for measuring instrument, see chapter „Calibration certificates“. DAkkS accredited calibration meets all the requirements regarding test resources laid down in DIN EN ISO/IEC 17025. Temperature drift Time constant