Abstract: A Coriolis flowmeter includes a change ratio obtainer configured to obtain a change ratio of vibration of a vibration tube when the vibration tube is vibrated with a constant driving force by causing a switch to select a fixed gain setting voltage, a calculator configured to calculate a first parameter indicating at least one of a spring constant of the vibration tube and a damping coefficient of the vibration tube on the basis of the change ratio obtained by the change ratio obtainer and the constant driving force, and a predictor configured to predict at least one of a time, an operating time, and an integrated flow rate of a fluid flowing in the vibration tube required for a state of the vibration tube to become a state requiring maintenance, using the first parameter calculated by the calculator or a second parameter obtained by performing a predetermined calculation on the first parameter.

Abstract: A field device configured to measure a state amount of a fluid as a measured value, the field device includes a slug flow detector configured to detect an occurrence of a slug flow, and a controller configured to hold a hold value of the measured value if the occurrence of the slug flow is detected by the slug flow detector, the hold value being a value based on at least one measured value in a predetermined period from a predetermined time before a time at which the slug flow has been detected.

Abstract: A Coriolis flowmeter includes a change ratio obtainer configured to obtain a change ratio of vibration of a vibration tube when the vibration tube is vibrated with a constant driving force by causing a switch to select a fixed gain setting voltage, a calculator configured to calculate a first parameter indicating at least one of a spring constant of the vibration tube and a damping coefficient of the vibration tube on the basis of the change ratio obtained by the change ratio obtainer and the constant driving force, and a predictor configured to predict at least one of a time, an operating time, and an integrated flow rate of a fluid flowing in the vibration tube required for a state of the vibration tube to become a state requiring maintenance, using the first parameter calculated by the calculator or a second parameter obtained by performing a predetermined calculation on the first parameter.

Abstract: A field device configured to measure a state amount of a fluid as a measured value, the field device includes a slug flow detector configured to detect an occurrence of a slug flow, and a controller configured to hold a hold value of the measured value if the occurrence of the slug flow is detected by the slug flow detector, the hold value being a value based on at least one measured value in a predetermined period from a predetermined time before a time at which the slug flow has been detected.

Abstract: A field device includes a first program area storing a first program, a second program area storing a second program designed such that if a program execution portion executes each of the first and second programs using the same data, a result of a calculation performed according to the second program is the same as a result of a calculation performed according to the first program, a first calculation result storage buffer storing a result of the calculation performed by the program execution portion according to the first program, and a second calculation result storage buffer storing a result of the calculation performed by the program execution portion according to the second program, and a calculation result comparator comparing the calculation result stored in the first calculation result storage buffer with the calculation result stored in the second calculation result storage buffer.

Abstract: A field device includes a first program area storing a first program, a second program area storing a second program designed such that if a program execution portion executes each of the first and second programs using the same data, a result of a calculation performed according to the second program is the same as a result of a calculation performed according to the first program, a first calculation result storage buffer storing a result of the calculation performed by the program execution portion according to the first program, and a second calculation result storage buffer storing a result of the calculation performed by the program execution portion according to the second program, and a calculation result comparator comparing the calculation result stored in the first calculation result storage buffer with the calculation result stored in the second calculation result storage buffer.

Abstract: There is provided a Coriolis mass flowmeter. The flowmeter is configured to vibrate a pipe line through which a fluid flows and measure a mass flow rate of the fluid flowing through the pipe line, based on a phase difference between an upstream vibration signal and a downstream vibration signal, wherein the upstream vibration signal is detected in an upstream side of the pipe line, and the downstream vibration signal is detected in a downstream side of the pipe line.

Abstract: There is provided a Coriolis mass flowmeter. The flowmeter is configured to vibrate a pipe line through which a fluid flows and measure a mass flow rate of the fluid flowing through the pipe line, based on a phase difference between an upstream vibration signal and a downstream vibration signal, wherein the upstream vibration signal is detected in an upstream side of the pipe line, and the downstream vibration signal is detected in a downstream side of the pipe line.