An SS pressure sensor will be used to measure the specific gravity of a flowing production liquid. Specific gravity is simply the ratio of liquid density to water density.
Figure shows how this can be measured by the difference in head pressure for equal heights of the liquid and water. A level control system maintains the flowing production liquid at the same level as the water.
The differential SS sensor has a sensitivity of 45 mV/kPa. The specific gravity will be measured in the range of 1.0 to 2.0. The liquid/water level is 1.0 m, and the density of water.
a. What is the pressure of water at the sensor? What is the range of pressure of the liquid at the sensor?
b. What sensor voltage results for the range of 1.0 to 2.0 specific gravity?
c. Develop signal conditioning to interface the sensor output to an 8-bit ADC with a 5.00-V reference.
d. What is the digital resolution in specific gravity measurement?
e. If the level control system has a -cm error about the setpoint, how much error will there be in specific gravity measurement?