Moisture content determination in solids - uses two electrodes which touch material and are connected to amplifier circuit feeding output to recorder

摘要

The electronic circuit for determining the moisture content of solids measures the resistance between two points on a test section of the material. Two electrodes touch the material and are connected to an amplifier circuit whose output is connected to a recording device indicating moisture content. The circuit is designed to ensure that the moisture percentage value display is almost linear so that the measurement signal can be directly processed digitally. A cascade amplifier is connected to the electrodes at its inputs and to an operational amplifier at its input. The operational amplifier is connected to the recording device via an optical coupler.