Patent ID: 7802462

Claim:
A gas flow stand ( 200 ), comprising: a weighing device ( 210 ); a meter under test ( 203 ) positioned on the weighing device ( 210 ); an outlet valve ( 204 ) positioned on the weighing device ( 210 ) and coupled to an outlet of the meter under test ( 203 ), wherein the outlet valve ( 204 ) can be closed; and a gas source ( 201 ) positioned on the weighing device ( 210 ); with the gas flow stand ( 200 ) configured to open the outlet valve ( 204 ) in order to introduce gas from the gas source ( 201 ) into the meter under test ( 203 ) and purge the meter under test ( 203 ), close the outlet valve ( 204 ) in order to charge the gas flow stand ( 200 ) to a predetermined pressure, weigh the gas flow stand ( 200 ) including the gas source ( 201 ) to obtain an initial weight of the gas flow stand ( 200 ) and gas, open the outlet valve ( 204 ) to create flow through the meter under test ( 203 ) substantially at the predetermined pressure, close the outlet valve ( 204 ) to stop the test, wherein the outlet valve ( 204 ) traps a trapped volume of gas within the meter under test ( 203 ), and weigh the gas flow stand ( 200 ) and the gas source ( 201 ) after the test in order to obtain a final weight, wherein a weight measurement comprises the gas flow stand ( 200 ) and the gas therein, including the trapped volume.