Selecting the right dewpoint meter for using in a compressed air application can be daunting, confusing and time consuming since many options and choices are available.
Vaisala DMT340 Series Dewpoint and Temperature Transmitter
It pays to conduct the dewpoint meter purchase selection process carefully as the choice can greatly influence the instrument’s stability and accuracy, resulting in the finished product’s quality.
A freely available App Note from Vaisala facilitates and guides the instrument selection process by answering four important questions that experts have found to be useful for measuring moisture in gases. This note will help to narrow down the options.
Buyers would have to first decide whether they require a portable or fixed platform.
They would then need to check the type of dryer being used by them. Having answered these two requirements, the buyers would need to know the temperature and pressure at the measurement location. Then they have to ascertain whether the measurement is made through a sample cell or directly in the line. This will help in narrowing down the buying options and eliminating unwanted instruments.
Dewpoint measurements are among the most crucial measurements for ensuring a dry and clean compressed air system. Such dewpoint measurements are possible on any place on the system’s supply or demand sides. Accordingly the instrument’s needs and application conditions are likely to vary to a large extent.
In addition, sensors must be able to withstand exposure to many contaminants, such as chemical impurities, water spikes, entrained compressor oil and ambient humidity.
All these situations can be handled by the Vaisala sensors. In addition, these sensors offer the quickest wet-to-dry response time and the lowest drift, enabling a two-year calibration interval.
The company’s application note on dewpoint instruments is available for download at
www.vaisala.com/files/Dew-point-compressed-air-Application-note-B210991EN-A.pdf. In the form of ‘frequently asked questions’ this PDF gives an insight into salient aspects of dew point instruments that is useful to buyers. The App Note highlights the important aspects of malfunctioning dewpoint sensors, knowledge and measurement of dewpoint in compressed air, range of dew point temperatures in compressed air, calibration and check of the dewpoint sensor, and so on.