LEVEL DETECTION CIRCUITRY
The density of the fluid, ambient temperature changes, and humidity are three factors which can
affect the accuracy and reliability of level detection instrumentation. Level detection circuit
operation is summarized below.
Circuit Operation Summary
There are three major reasons for utilizing remote level indication:
Level measurements may be taken at locations far from the main facility.
The level to be controlled may be a long distance from the point of
The level being measured may be in an unsafe/radioactive area.
The basic block diagram of a differential pressure level instrument are:
A differential pressure (D/P) transmitter which consists of a diaphragm
with the high pressure (H/P) and low pressure (L/P) inputs on opposite
sides. As the differential pressure changes, the diaphragm will move.
The transducer changes this mechanical motion into an electrical signal.
An amplifier amplifies the electrical signal generated by the transducer
and sends it to the level indicator.
A level indicator displays the level indication at a remote location.