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testo 6681 - Temperature/humidity transmitter for critical, demanding applications

0555 6681
  • Maximum measuring accuracy thanks to reliable and long-term stable humidity sensor technology
  • Ethernet, relay and analog outputs enable optimum integration into individual automation systems
  • Suitable special probes for high-humidity and trace humidity applications and aggressive media
  • Robust, easy-to-clean metal housing
  • Ideal for industrial humidity measurement: With professional measuring technology, maximum precision and practical features, the testo 6681 humidity transmitter, in combination with the testo 6610 probe series, is impressive even when it comes to demanding measuring tasks, e.g. in drying and air conditioning technology, high humidity or trace humidity applications.

    The testo 6681 temperature and humidity transmitter is ideal for monitoring critical climate values in industrial processes or in research. The transmitter is designed for use in industry and is a reliable partner in trace humidity and compressed air process technology, drying and air conditioning technology.

    Areas of application for the testo 6681 temperature and humidity transmitter

    • Drying processes (e.g. drying tobacco, drying ceramics)
    • Painting installations
    • Food production (e.g. cheese processing, ripening fruit, drying pasta, mushroom cultivation)
    • Bio research
    • High-humidity applications
    • Sterilization processes in an H2O2 environment
    • Cleanrooms

    Technical highlights of the testo 6681 climate transmitter

    • Maximum measuring accuracy up to ±(1.0 + 0.007 x reading)
    • Reliable and long-term stable humidity sensor
    • Ethernet*, relay and analog outputs allow for versatile use, e.g. for control purposes (optionally 2 or 3 analog outputs), for direct activation of air-conditioning units (optionally via relay) or even in indoor climate monitoring systems (optionally via Ethernet connection)
    • Options for self-monitoring and early warning ensure a high level of system availability
    • Robust metal housing and water jet protection according to IP65
    • Optional 2-line display enables commissioning, adjustment and analysis without using a PC

    Enjoy all the benefits with the practical accessories

    • Wide range of high-quality digital probes available: To commission the transmitter, you need a connectable probe. Use, for example, probes for high humidity or trace humidity measurement, probes for aggressive media
    • Smart probe technology: Easy probe replacement, digital interface to the transmitter, intelligent calibration concept
    • Optional protective probe caps available for special applications (made of stainless steel, PTFE, wire mesh filter, metal, or a patented H2O2 protective cap)
    • Quick and easy commissioning and maintenance using the P2A software for parametrization, adjustment and analysis

    • testo 6681 humidity/temperature transmitter including instruction manual
    • Factory certificate

    Note: Please keep in mind that you need an attachable probe to commission the transmitter.

    * When using the Ethernet function, we recommend ordering the P2A software in order to be able to make the network settings.


  • Accessories
    P2A PC software
      0554 6020
    • Accessories
      Pressure-tight screw connection with PTFE ring
        0554 1796
      • Accessories
        Ethernet connector
          0554 6653