The SMT Condensation Sensor is used to detect the presence of small amounts of water or ice by measuring the dielectric constant of the medium surrounding the sensor. The non-invasive sensor is perfect for monitoring condensation, frost, and moisture content levels in wood, concrete and stone. 
 
Horizontal planar sensing elements couple to water ions through a fringing electric field. When condensation or frost forms on the sensing grid, the electric field passes through the ions, which act as the dielectric medium of the capacitor.
 
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