Patent ID: 8412471

Claim:
A measuring instrument comprising: a differential pressure sensor sensing a pressure differential between fluids; an environment sensor sensing a physical quantity that indicates a change in an environment that has an effect on the differential pressure sensed by the differential pressure sensor; a first A/D converting device, which receives a supply of a power supply voltage and is in a constantly operating state, converting an inputted analog signal from the differential pressure sensor into a digital signal; a second A/D converting device, which receives a common power supply voltage, with the power supply voltage to the first A/D converting device being the common power supply voltage, to be in a constantly operating state, converting an inputted analog signal from the environment sensor into a digital signal; and a processing device sampling, with a first period, an A/D converted value that has been converted into the digital signal by the first A/D converting device, and for sampling, with a second period that is longer than the first period, an A/D conversion value that has been converted into the digital signal in the second A/D converting device.