Answer / d tilston

Absolute pressure is zero when the pressure is that of a
pure vacuum. There can never be a negative absolute pressure.
Gauge pressure is zero when the pressure equals the air
pressure outside the container being measured. If that
pressure is less then the ambient pressure, then it is
considered a negative gauge pressure.

Answer / samir

Absolute Pressure= Atmospheric Pr.+ Gauge Pr.

i have used level transmitter in starch cooking preparation tank. tank total height 2mtr.sometime LT display shows some error value when tank is fully empty and diaphragm side i already checked okay no problem in diaphragm area. field cable checked 24volt and mA shows correct value while tank empty mA is 4mA. 4mA i needed that 0% but display showing 10% or 15% percentage values are varying continously please give any good solution for me.....

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