Multivariable transmitter and computation processing method of the same

• US 20050125190A1
• Filed: 12/03/2004
• Published: 06/09/2005
• Est. Priority Date: 12/05/2003
• Status: Active Grant

• Current Assignee: Yokogawa Electric Corporation
• Original Assignee: Yokogawa Electric Corporation
• Inventors: Nakagawa, Masaru, Koyama, Etsutaro, Ito, Akio, Suzuki, Atsuko
• Granted Patent: US 7,584,063 B2
• Time in Patent Office: Days
• US Class Current: 702/127
• CPC Class Codes: G01D 1/00 Measuring arrangements giving results other than momentary value of variable, of general application G01D3/00 takes precedence; in tariff metering apparatus G01D4/00; transducers not specially adapted for a specific variable G01D5/00
• CPC Class Codes: G01F 1/50 Correcting or compensating means
• CPC Class Codes: G01F 15/024 involving digital counting

Abstract

A multivariable transmitter has a microprocessor for executing a computation processing task with using a plurality of physical quantity signals. The microprocessor executes a processing for obtaining data from a sensor every computation processing task and executes the computation processing task in a time-division manner.

Claims

1. A multivariable transmitter comprising:

a single microprocessor for executing a plurality of computation processing tasks with using a plurality of physical quantity signals,

wherein the microprocessor executes the plurality of computation processing tasks in a time-division manner.

2. The multivariable transmitter according to claim 1,

wherein the computation processing tasks include a computation selecting processing which selects a processing item to be executed during each computation period.

3. The multivariable transmitter according to claim 2,

wherein the computation processing tasks include a computation processing task to be divided and executed through a plurality of computation periods.

4. The multivariable transmitter according to claim 3,

wherein the computation processing tasks include computation processing tasks for calculating a differential pressure value and a static pressure value regarding a fluid to be measured.

5. The multivariable transmitter according to claim 4,

wherein the computation processing tasks include a flow rate computation processing task based on the differential pressure value, the static pressure value and a temperature value regarding the fluid to be measured.

6. The multivariable transmitter according to claim 5,

wherein the computation processing tasks include a communication processing computation task for transferring physical quantity data or computed data to a higher equipment by means of communication and obtaining various types of data from the higher equipment.

7. The multivariable transmitter according to claim 6,

wherein a sensor for detecting the physical quantity is a resonant-type pressure sensor which has a single pressure sensitive diaphragm and detects differential pressure and static pressure by means of computation.

8. A multivariable transmitter comprising:

a microprocessor for executing a computation processing task with using a plurality of physical quantity signals,

wherein the microprocessor executes a processing for obtaining data from a sensor every computation processing task and executes the computation processing task in a time-division manner.

9. The multivariable transmitter according to claim 8,

wherein the computation processing tasks include a computation selecting processing which selects a processing item to be executed during each computation period, and a process temperature value computation processing task to be divided and executed through a plurality of computation periods.

10. The multivariable transmitter according to claim 9, further comprising:

a table that shows a setting provided by a combination of a selection by the computation selecting processing and a division processing function.

11. The multivariable transmitter according to claim 10,

wherein the sensor is a resonant-type pressure sensor which outputs a first resonance frequency and a second resonance frequency.

12. The multivariable transmitter according to claim 11, further comprising:

a resistance temperature sensor provided in an atmosphere of a process temperature; and

a nonvolatile data table for storing resistance values of the resistance temperature sensor and temperature values corresponding to the resistance values,

wherein the microprocessor calculates a temperature value by an interpolation computation based on the resistance values and the data table.

13. The multivariable transmitter according to claim 12,

wherein the resistance values are formed at intervals in the data table, and a linear interpolation equation is used for the interpolation computation.

15. The multivariable transmitter according to claim 8, further comprising:

a resistance temperature sensor provided in an atmosphere of a process temperature; and

a nonvolatile data table for storing resistance values of the resistance temperature sensor and temperature values corresponding to the resistance values,

wherein the microprocessor calculates a temperature value by an interpolation computation based on the resistance values and the data table.

16. The multivariable transmitter according to claim 15,

wherein the resistance values are formed at intervals in the data table, and a linear interpolation equation is used for the interpolation computation.

14. A computation processing method of a multivariable transmitter which executes a plurality of computation processing tasks with using a plurality of physical quantity signals, comprising the steps of:

setting a computation selection switch which assigns a computation selection and a division processing;

executing a processing for obtaining data from a sensor; and

executing a processing in a case that a computation is executed by the computation selection switch.