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testo 645 - Humidity/temperature measuring instrument

0560 6450
  • High-precision humidity measurement up to ± 1% RH
  • Internal reading memory (3,000 readings)
  • Convenient data evaluation via optional PC software
  • Possibility of attaching a really wide range of optional probes thanks to a large accessory portfolio
  • The testo 645 humidity/temperature measuring instrument automatically indicates the measurement parameters of relative humidity, absolute humidity, dew point, degree of humidity, enthalpy and temperature at the touch of a button.
    The testo 645 high-precision humidity and temperature measuring instrument offers two probe inputs for attaching a comprehensive range of probes:
    • Channel 1: temperature probe, type K/J/S, NTC
    • Channel 2: humidity/temperature probe or Pt 100 temperature probe

    At the touch of a button, the thermohygrometer automatically indicates the measurement parameters of temperature, relative humidity, dew point, pressure dew point, absolute humidity, degree of humidity and enthalpy, along with min., max. and mean values, as well as the last measured value. Convenient evaluation of the measurement data is possible using the optional PC software. Measurement data can also be printed out directly at the measuring location via the optional testo fast printer.

    Areas of application of the testo 645 humidity/temperature measuring instrument

    • Monitoring of temperature and humidity values in production, storage and server rooms, museums, archives, cold stores, containers and display cases
    • Location of mould formation in residential or other buildings 

    testo 645 humidity/temperature measuring instrument, including battery.

    Temperature - Pt100

    Measuring range
    -200 to +800 °C
    Accuracy
    ±0.1 % of mv (200.1 to 800 °C)
    ±0.2 °C (-200 to 200 °C)
    Resolution
    0.1 °C

    Temperature - NTC

    Measuring range
    -50 to +150 °C
    Resolution
    0.1 °C

    Temperature - TC Type K (NiCr-Ni)

    Measuring range
    -200 to +1370 °C
    Accuracy
    ±0.5 % of mv (-200 to -60.1 °C)
    ±0.5 % of mv (+60.1 to +1370 °C)
    ±0.3 °C (-60 to +60 °C)
    Resolution
    0.1 °C

    Accessories: Humidity probes

  • Accessories: Humidity probes
    Extension cable
    Extension cable
      :
      0409 0063
    • Accessories: Humidity probes
      Connection cable
      Connection cable
        :
        0430 0143
      • Accessories: Humidity probes
        saline solution pot
        testo saline solution pot for checking humidity probes, 33 %RH
          :
          0554 0636
        • Caps for humidity probes

        • Caps for humidity probes
          Edelstahl-Sinterkappe, Ø 21 mm
          Stainless steel sintered cap, Ø 21 mm, can be screwed onto humidity probe
            :
            0554 0640
          • Caps for humidity probes
            Sintered stainless steel filter
              :
              0554 0641
            • Caps for humidity probes
              PTFE sintered filter, Ø 21 mm, for corrosive substances
              PTFE sintered filter, Ø 21 mm, for corrosive substances
                :
                0554 0666
              • Caps for humidity probes
                Metal protection cap
                  :
                  0554 0755
                • Caps for humidity probes
                  Sintered PTFE filter,
                  Sintered PTFE filter, Ø 12 mm, for corrosive media
                    :
                    0554 0756
                  • Caps for humidity probes
                    Wire mesh filter
                      :
                      0554 0757
                    • Humidity probes

                    • Humidity probes
                      No picture available
                      Humidity/temperature probe
                        :
                        0636 9742
                      • Probes

                        Pt100 temperature probes

                      • Pt100 temperature probes
                        Standard immersion/penetration probe
                          :
                          0604 0273
                        • Pt100 temperature probes
                          Highly accurate immersion/penetration probe
                          Highly accurate immersion/penetration probe
                            :
                            0628 0015
                          • Pt100 temperature probes
                            0628 0016
                            Flexible precision immersion probe, cable heat-proof up to +265 °C
                              :
                              0628 0016
                            • Type K (NiCr-Ni) probes

                              Additional accessories and Spare parts

                            • Additional accessories and Spare parts
                              Extension cable
                              Extension cable
                                :
                                0409 0063
                              • Additional accessories and Spare parts
                                Connection cable
                                Connection cable
                                  :
                                  0430 0143
                                • Additional accessories and Spare parts
                                  Sintered stainless steel filter
                                    :
                                    0554 0641
                                  • Additional accessories and Spare parts
                                    Control and adjustment set for Testo humidity probes
                                    Control and calibration kit for Testo humidity probes
                                      :
                                      0554 0660
                                    • Additional accessories and Spare parts
                                      Sintered PTFE filter,
                                      Sintered PTFE filter, Ø 12 mm, for corrosive media
                                        :
                                        0554 0756
                                      • Certificates

                                        Printer and accessories

                                      • Printer and accessories
                                        testo-Schnelldrucker IRDA mit kabelloser Infrarot-Schnittstelle
                                        testo fast printer IRDA
                                          :
                                          0554 0549
                                        • Printer and accessories
                                          Spare thermal paper
                                          Spare thermal paper for printer, permanent
                                            :
                                            0554 0568
                                          • Software and Accessories

                                          • Software and Accessories
                                            RS232
                                            RS232 cable
                                              :
                                              0409 0178
                                            • Transport and Protection