The immersion probe comprises a measuring cell, two wire transmitter and a special cable with capillary tube. The housing comprises stainless steel with a pressure-sensitive diaphragm that is protected with a stainless steel cap.
The level signal is determined by the pressure difference between the water column over the probe and atmospheric pressure which is transferred to the probe through the capillary tube.
This differential pressure is converted to a 0 to 4 mA Analog signal by the piezo-resistive cell and the fitted electronics.