Temperature/Humidity Transmitters

Industrial humidity measurement requires absolute professionalism in measuring and control technology. In industrial processes or in research-based business, the testo 6681 temperature and humidity transmitter is ideal wherever critical climatic values need to be maintained. The climate transmitter boasts a high-precision humidity sensor with long-term stability (optionally available), which enables it to achieve maximum precision: up to ±(1.0 + 0.007 * reading)

Precise measuring and control technology will help you to accurately optimize the climatic conditions in your rooms in order to prevent process disruptions and quality losses. Automation systems result in particularly efficient processes. The testo 6681 temperature and humidity transmitter can easily be integrated into individual automation systems because it features Ethernet, relay and analog outputs.

Areas of application for the testo 6681 temperature and humidity transmitter

1. Drying processes (e.g. drying tobacco, manufacturing ceramics, drying roofing tiles)
2. Painting installations
3. Food production (e.g. cheese processing, ripening fruit, drying pasta)
4. Bio-research
5. Breeding mushrooms
6. High-humidity specialist fields
7. Sterilization processes in an H2O2 environment
8. Clean rooms
9. Museums
10. Storing hygroscopic substances
11. Storing electronic components

Technical highlights of the testo 6681 climate transmitter

1. High-quality digital probes available for the temperature and humidity transmitter: e.g. high-precision Testo humidity sensor with long-term stability, probe for high-humidity measurement, probe for trace humidity measurement, probe with a self-monitoring function (for measuring in sensor-damaging media)
2. Smart probe technology: probe can be changed by the user, digital interface for the temperature and humidity transmitter, intelligent calibration concept
3. Ethernet, relay and analog outputs allow for versatile use of the temperature and humidity transmitter: e.g. for control purposes (2 or optionally 3 analog outputs), for direct activation of units in the air conditioning system (optionally via relay) or even in climate monitoring systems (optionally via Ethernet connection)
4. P2A software for parametrization, adjustment and analysis saves time and money during commissioning and maintenance
5. Optimum protection: the climate transmitter features a robust metal housing and is protected against water jets according to protection class IP 65. Protective caps are also optionally available for specific applications (made of stainless steel, PTFE, wire mesh filter or metal). A patented H2O2 protective cap is also available to order
6. 2-line display: the climate transmitter is optionally available with a display, enabling you to undertake commissioning, adjustment and analysis without using a PC
7. Options for self-monitoring and early warning function: guarantees high system availability

In combination with the right probe, the testo 6681 temperature and humidity transmitter offers superior properties and benefits in comparison with a conventional climate transmitter because, when it comes to temperature and humidity measurement, this instrument features supreme, cutting-edge technology.

Note: Please note that the transmitter can only be operated with a probe. The probes are optionally available

Adjustment on-site: Fast and precise via the external interface!
Of interest not only to in-house technicians or Facility Managers, but increasingly also to the responsible plant constructors: Which follow-on costs arise as a result of this transmitter?
Good news from Testo: The testo 650 or testo 400 reference instruments can be connected using the adapter 0554 6022 via the external interface – without opening the transmitter. A few operating steps in the testo 400 or testo 650 menu suffice to adjust the testo 6621 transmitter. Conclusion: Saved time and lower operating costs!

A broad variety of the testo 6621 transmitter is available. Depending on the application in a room or in a duct, the corresponding designs can be selected. A display and an external probe are available as options. You can choose between the housing colours grey and white. The testo 6621 is persuasive in technical terms thanks to the patented humidity sensors that guarantee the highest accuracy. The sensors and the analog outputs can be adjusted, analyzed and parameterized via the external interface using the P2A software.
The testo 6621 is a high-performance transmitter for a low price. It meets the increasing requirements in automated building services in terms of accuracy, reliability and safety and thereby saves energy costs.

- Highly accurate testo humidity sensor with long-term stability (±2.0% RH)
- Optional 2-line LCD display
- P2A software for parameterization, adjustment and analysis, saves time and costs in commissioning and maintenance
- Optimum calibration concept thanks to adjustment of the entire signal chain (1-point, 2-point and analog adjustment)
- Adjustment without dismantling the transmitter
- 2 analog outputs (humidity/temperature), option of 1 passive humidity and temperature analog output

Product Description

Not all measurement problems can be solved with "simple" transmitters. The testo 6651 meets special challenges. When combined with the probe series testo 660x, the testo 6651 becomes the first choice in demanding air conditioning technology as well as in many other applications. Optimum adjustment concept thanks to adjustment of the entire signal chain incl. analog adjustment Ethernet, relay and analog outputs allow optimum integration into individual automation systems Self-monitoring and early warning guarantee high system availability. Calculation and presentation of the humidity parameters relative humidity absolute humidity and dewpoint. P2A software for parameterization, adjustment and analysis saves time and costs in commissioning and maintenance
Display with multi-language display. High-quality plastic housing

The testo 6631 transmitter was developed specially for monitoring critical ambient conditions in greenhouses, e.g. for bio research purposes. Precise and reliable humidity measurement is indispensible in these applications, in order to avoid costs caused by failed experiments.
Process security and system availability, among the most important factors in experimental plants, are supported by a number of properties of the testo 6631 bio research transmitter