A product which can be measured changes the characteristics of an electromagnetic field. The changed characteristics (energy and propagation speed) are measured and give information on the number of water molecules and existing mass.
Number of water molecules + admitted of mass = proportional moisture.
Due to the compensation of all well-known measured variables (temperature, density, ageing) the procedure is very exact and is comparable with a drying oven procedure.
The installation can be done mechanically (e.g. in side panel or chute) and electrically by the customer. One may prepare with some briefing of the process, as training is usually conducted by Döscher & Döscher.
Different versions with measuring frequencies from 10Hz to 500 cycles per second exist. For measurements of flowing bulk material usually 10 cycles per second are sufficient. Faster current production processes, e.g. paper webs, need a higher frequency to ensure a sufficient number of measurements per meter.
Desired solutions for special applications are developed based on the broad practical knowledge and scientific know-how of Döscher & Döscher. The spectrum of customized solutions ranges from equipment modification to research and development projects of several years.
The 2-PMR-method measures surface and core moisture independently of colour, as microwaves also penetrate the inside of a product where dampness can be measured. The procedure works, unlike some other microwave procedures, density-independently. The sensor structure with patented integrated reference resonator makes a long-term-stable measurement possible under changing site conditions.
Water is contained in nearly all materials; therefore these measuring systems are used in diverse industries, with an emphasis on the food, wood, coffee, tobacco, chemical and pharmaceutical industries.
The online support works as indicated in control terminal service of a PC with Windows 7 or Windows XP operating system. This computer is equipped at the factory already with one ISDN/DSL-card, dependent on the telephone network of the customer. After connection of the PC's the service department receives a direct connection to the measuring instrument and can, in co-operation with the customer, clarify questions or changing requirements. This service is available world-wide.
It´s also possible to make online support via Internet (TCP/IP).
We offer the possibility of measuring samples of your product here first in-house. With the samples, a calibration is provided and accomplished via reproductibility test. These results are decisive for the order and specification of the measuring system. If the results of practical application are not achieved within four weeks the system may be returned.
The possible measuring range depends on the product properties and the sensor selected for it. Usually it ranges from 0-20%. Nearly all dried products lie within this measuring range and regulation/control of a dryer is possible.