Patent ID: 7251998

Claim:
A system for measuring the weight of a liquid in a tank subject to tilting, comprising: a plurality of differential pressure transducers located outside the tank, each pressure transducer having a first pressure port and a second pressure port, each pressure transducer providing at least one output signal responsive to the pressures applied to the first pressure port and the second pressure port; a plurality of probes spaced apart in the tank at locations selected such that tilting of the tank causes a height of liquid at a first location of at least a first probe to increase and causes a height of liquid at a second location of at least a second probe to decrease, each probe comprising: a first tube having a first end located inside the tank proximate to the bottom of the tank and having a second end coupled to the first port of a respective one of the pressure transducers to communicate a pressure to the pressure transducer, the pressure caused by weight of liquid above the first end; and a second tube having a first end located inside the tank in the ullage above the level of liquid in the tank and having a second end coupled to the second port of the respective one the pressure transducers; and a processing system coupled to receive signals responsive to the output signals from the plurality of pressure transducers, the processing system calculating a quantity of liquid in the tank based on the respective weights of liquid above each of the plurality of probes.