Suppose an instrument salesperson comes to your shop and tells you his company’s radar level transmitter product is superior to all hydrostatic and displacer level transmitters because those instruments’ accuracy depends on a fixed process liquid density, whereas radar transmitters do not.
Thus, he tells you, his radar transmitters will give accurate level measurements even when process pressures and temperatures change.
What do you think of this claim? Is the salesperson’s claim true, or not? Explain.
If a magnetostrictive level transmitter salesperson made a comparable claim – that the accuracy of a magnetostrictive instrument would not be affected by changes in process liquid density – would you believe it?
Caveat emptor! (Latin for “buyer beware”)
Radar level transmitters are definitely affected by certain properties of the gas or vapor above the liquid surface.
I’ll let you identify what those properties are!
Share your answers and explanation with us through the below comments section.
Credits: Tony R. Kuphaldt