Patent ID: 7171852

Claim:
A tracking assembly for tracking the operation of a rotary gas meter in the presence of a gas flow having a driven member adapted to be directly driven by the gas flow, the gas meter being provided with an electronic compensator for measuring flow volume on a first end of the gas meter, the tracking assembly providing a backup measurement of the volume of gas flow through the rotary gas meter for the electronic compensator, said tracking assembly comprising: (a) a backup mechanical counter adapted to be coupled to the driven member on a second end of the gas meter, such that the backup mechanical counter is located on the opposite end of the gas meter from the electronic compensator and operates independently of the electronic compensator, such that when the backup mechanical counter is coupled to the driven member, the backup mechanical counter generates a value that is directly proportional to the number of rotations of the driven member; (b) means for providing a conversion factor associated with the gas meter; and (c) means for multiplying the value generated by the backup mechanical counter by the conversion factor to determine a backup measurement of the volume of gas that has been displaced by the gas meter which can be utilized in case of failure of the electronic compensator.