Trace humidity transmitter
Air, compressed air and gases are used in all areas of industry. Humidity is normally undesirable because it can cause mechanical damage, corrosion or adhesion of the material, which can increase the operating costs or even impair the quality of the end product. The international standard ISO 8573 defines seven classes of compressed air quality based on moisture content, oil content and particle content. The main way of reaching and ensuring compliance with a quality class involves installing a suitable dryer. Pressure dewpoint transmitters/switches are used to monitor the dryer and its results.

testo 6781 (Pressure dewpoint transmitter)
The new pressure dewpoint transmitter testo 6781 completes the product range for monitoring trace humidity in compressed air and enlarges the measurement range down to -90 °Ctd (see below graphic).
Overview of features and benefits:
Pressure dewpoint measurement in the ISO Classes 1 (<-70 °Ctd) and 2 (<-40 °Ctd)
Monitoring of adsorbtion dryers, granulate dryers and medical compressed air
Quality assurance for noble gas preparation