What is a sheath on a probe used for?
A sheath on a probe is used to deaden the upper portion of a probe. A sheath should always be used when inserting a probe through a stand-pipe or nozzle in order to negate unwanted capacitance changes resulting from condensate. Otherwise, significant measurement errors will occur. A sheath can also be used to deaden the upper portion of a probe that is not being used for level measurement (above the 100% span point or above the point level set point); this will eliminate the errors typically caused by condensate or changing air/vapor conditions. A sheath is always shorter than the overall length of the probe.
