Yokogawa Electric Corporation

Toru Shimura

Ikuhiko Ishikawa

Junichi Iwashita

Yasumi Koike

Daisuke Harigane

Shinnosuke Yoshida

Wandong Li

Hong Yan Zhang

Gouki Nakayama

In order to improve the adaptability of diagnosis of an operating state of a field device, a field deviceaccording to the present disclosure has a diagnoserconfigured to diagnose an operating state of the field deviceby hierarchically implementing a plurality of diagnostic processes. The diagnosercan select whether to enable or disable a diagnostic result of at least one diagnostic process of a plurality of diagnostic processes in a diagnostic process after the one diagnostic process.

Field device, method of diagnosing field device and diagnostic apparatus

A field device, which measures a physical quantity in a plant or processes the physical quantity, includes: an instruction unit configured to output a verification execution instruction signal for instructing execution of verification of the field device; an operation verifying unit configured to verify an operation of at least one element of the field device in response to the verification execution instruction signal and to verify an operation of the field device based on the verification result; and an output unit configured to output the verification result which is a result of verification of the operation by the operation verifying unit.

Field device

An electromagnetic flow meter includes a flowtube including a coil disposed in the vicinity of a measurement tube, and electrodes disposed on the measurement tube, a converter including an excitation unit configured to generate an excitation signal and output the excitation signal to the coil through an excitation cable, and a detection signal receiving unit configured to receive a detection signal from the electrodes through a signal cable, and generate a flow rate signal, and a miswiring detection unit configured to perform miswiring diagnosis on the excitation cable or the signal cable on the basis of a difference between a change amount of the flow rate signal when the excitation signal is being output and a change amount of the flow rate signal when the excitation signal is not being output.

Electromagnetic flow meter and miswiring detection method

A drive circuit includes a primary power supplier which supplies a primary electric power in accordance with a state of the drive circuit, a secondary power supplier which supplies an operation electric power and an excitation electric power, an excitation current supplier which supplies an excitation current to an excitation coil, a power supply monitor which compares the voltage value of the operation electric power with a voltage threshold and outputs monitoring information, and a controller which determines whether a short circuit has occurred in the excitation coil based on the monitoring information, and stops supplying the excitation current if the short circuit has occurred. The voltage threshold is higher than a lowest voltage value with which the controller operates, and the voltage threshold is a voltage value representing that the short circuit has occurred in the excitation coil.

Drive circuit and electromagnetic flowmeter

A field device according to one aspect of the present invention includes a sensor, an analog-digital converter configured to continuously convert detected signals output from the sensor to digital signals, and a calculator configured to convert the digital signals to process values. The calculator starts acquisition of the digital signals output from the analog-digital converter at a first point in time that is delayed by a processing time required for the conversion process of the analog-digital converter from a start point of a timing signal defining a sampling section of the detected signals, and finishes the acquisition of the digital signals output from the analog-digital converter at a second point in time that is delayed by the processing time from an end point of the timing signal.

A first detection electrode that outputs a first flow rate signal and a second detection electrode that outputs a second flow rate signal, a differential circuit that outputs a differential flow rate signal obtained by obtaining a difference between the first flow rate signal and the second flow rate signal, an AC signal generation circuit that causes a first AC current to flow between the first detection electrode and the ground electrode and causes a second AC current with a reverse phase at the same frequency as that of the first AC current to flow between the second detection electrode and the ground electrode, and a diagnosis unit that diagnoses an abnormality of at least either of the first detection electrode or the second detection electrode based on a differential flow rate signal.

Electromagnetic flow meter

A flowmeter includes an exciter configured to excite fluid which is a measurement target, a state detector configured to detect a state of the fluid excited by the exciter, a driver configured to supply exciting current for driving the exciter, a first current detector that is disposed between the exciter and the driver, the first current detector being configured to detect the exciting current, and a processor configured to diagnose insulation deterioration of the exciter in accordance with a change of a detection result of the first current detector.

Flowmeter, insulation deterioration diagnosis system, and insulation deterioration diagnosis method

An electromagnetic flow meter includes a converter including an excitation unit configured to generate and output an excitation signal and a flow rate signal receiving unit configured receive a flow rate signal, a flowtube including a coil connected to the excitation unit through an excitation cable and an electrode connected to the flow rate signal receiving unit through a signal cable, and a miswiring detection unit configured to enable the excitation unit to output an excitation signal of a first frequency and to calculate a first index value relating to the first frequency and a second index value relating to a second frequency from a flow rate signal acquired when the excitation signal of the first frequency is output. The miswiring detection unit determines that a miswiring occurs when the first index value is not large enough to satisfy a predetermined criterion than the second index value.

Electromagnetic flow meter, miswiring detection apparatus and miswiring detection method

An electromagnetic flowmeter for giving a magnetic field to a measurement fluid, detecting an electric signal occurring in the measurement fluid according to the magnetic field, and computing a flow quantity value based on the electric signal includes a zero point measurement section for measuring a zero point of the measurement fluid; a storage section for storing the measured zero point measurement value; a determination section for determining whether or not the difference between the preceding zero point measurement value stored in the storage section and the present zero point measurement value is beyond a predetermined value range; and at least either a transmission section for transmitting the determination result or a display section for displaying the determination result when the determination section determines that the difference is beyond the predetermined value range.

Electromagnetic flowmeter and zero point measurement method thereof

A field equipment includes: a signal processing section; a first calculation control section for generating a first control signal which controls a start of a signal processing of the signal processing section; first and second insulating sections coupled to the first calculation control section; and a second calculation control section coupled to the first and second insulating sections and the signal processing section, the second calculation control section receiving the first control signal and then transmitting a second control signal corresponding to the first control signal to the signal processing section. The signal processing section generates a processed signal based on the second control signal. The second calculation control section receives the processed signal, then transmits data related to the first signal to the first calculation control section via the second insulating section, and then shifts to a low power consumption mode.

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Musashino, Japan

Toru Shimura