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Press Release September 2018

Precise measurement of continuously high relative humidity over the network

The Web-Thermo-Hygrometer ++ from Wiesemann & Theis GmbH detects and monitors measurement values for temperature and relative humidity and makes them available over various network interfaces. The drift-free sensor for relative humidity shows no saturation effects and is thus ideal for precise long-term measurements even in environments with continuously high relative humidity. With measurement deviations of just 0.1K and 0.5% RH both sensors are very precise.

The Web-Thermo-Hygrometer ++ is an autonomous data logger for temperature and relative humidity. Data access and configuration are via the web browser. Depending on the storage interval the Web-Thermo-Hygrometer ++ collects data over measurement periods of between 12 weeks and 20 years.

The humidity sensor used shows no saturation effects even in continuous use in humid climates, thus enabling precise measurements in areas such as plant nurseries, ripening chambers, in fruit and vegetable storage facilities as well in various applications including the textile, wood or paper industries. The Web-Thermo-Hygrometer ++ is also suitable for outdoor use. The device is supplied on request with an additional calibration certificate (ISO or DAkkS).

When critical conditions arise, such as exceeded minimum or maximum values, the device triggers configurable actions. These include the sending of email alarms, SNMP traps and/or the IoT protocol MQTT.

A variety of communication protocols permits uncomplicated integration into SCADA, network management or MES systems. MQTT and REST capability means protocols are available for linking to the Internet of Things and for use in Industry 4.0 applications. Access to network sockets and the HTTP interface means that the development of custom solutions is supported.

The drift-free Web-Thermo-Hygrometer ++ is immediately available for a net price of 1298.00€. Commercial users can try out the device for a period of four weeks at no charge.

Wiesemann & Theis GmbH was founded in 1979 by Reinhard Wiesemann and Rüdiger Theis. 50 employees at the Wuppertal headquarters produce microcomputer and network technology. In 2001 Wiesemann & Theis were the first to introduce an industrial temperature sensor with network interface, and have for more than fifteen years been specializing in solutions from the realm of Industry 4.0.

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Drift-free Web-Thermohygrometer (W&T) The Web-Thermo-Hygrometer ++ detects and monitors measurement values for temperature and drift-free relative humidity.