PROCESS FLUID PRESSURE TRANSMITTER WITH PRESSURE TRANSIENT DETECTION

• US 20090139346A1
• Filed: 11/26/2008
• Published: 06/04/2009
• Est. Priority Date: 11/29/2007
• Status: Active Grant

• Current Assignee: Rosemount Incorporated (Emerson Electric Company)
• Original Assignee: Rosemount Incorporated (Emerson Electric Company)
• Inventors: Wehrs, David L., LeCuyer, Gregory J., VanderSanden, Steve, Perry, Dale H., Klosinski, Andrew J.
• Granted Patent: US 7,996,161 B2
• Time in Patent Office: Days
• US Class Current: 73/861.610
• CPC Class Codes: G01L 19/00 Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges

Abstract

A process fluid pressure transmitter includes a process fluid pressure sensor, measurement circuitry, a controller and a loop communicator. The process fluid pressure sensor has an electrical characteristic that varies with process fluid pressure. The pressure sensor is coupleable to a source of process fluid pressure. The measurement circuitry is coupled to the process fluid pressure sensor and provides a signal indicative of the electrical characteristic of the process fluid pressure sensor. The controller is coupled to the measurement circuitry and receives the signal and calculates a process fluid pressure based at least in part upon the signal. The controller is also configured to detect a process fluid pressure transient and store at least one parameter related to the process fluid pressure transient. The loop communicator is coupled to the controller and is configured to provide a signal over a process communication loop based upon the process fluid pressure. The process fluid pressure transmitter is also configured to provide an indication related to the at least one stored parameter.

Claims

1. A process fluid pressure transmitter comprising:

a process fluid pressure sensor having an electrical characteristic that varies with process fluid pressure, the pressure sensor being coupleable to a source of process fluid pressure;

measurement circuitry coupled to the process fluid pressure sensor, the measurement circuitry providing a signal indicative of the electrical characteristic of the process fluid pressure sensor;

a controller coupled to the measurement circuitry to receive the signal and calculate a process fluid pressure based at least in part upon the signal, the controller being configured to detect a process fluid pressure transient and store at least one parameter related to the process fluid pressure transient;

a loop communicator coupled to the controller, the loop communicator being configured to provide a signal over a process communication loop based upon the process fluid pressure; and

wherein the process fluid pressure transmitter is configured to provide an indication related to the at least one stored parameter.

2. The process fluid pressure transmitter of claim 1, wherein the process fluid pressure sensor is an absolute pressure sensor.

3. The process fluid pressure transmitter of claim 1, wherein the process fluid pressure sensor is a gage pressure sensor.

4. The process fluid pressure transmitter of claim 1, wherein the process fluid pressure sensor is a differential pressure sensor.

5. The process fluid pressure transmitter of claim 1, wherein both the process fluid pressure and transient detection are performed based on measurements from a single pressure sensor.

6. The process fluid pressure transmitter of claim 1, wherein the controller is embodied upon a feature board disposed within an electronics enclosure of the pressure transmitter.

7. The process fluid pressure transmitter of claim 1, wherein the loop communicator communicates the process fluid pressure in accordance with a process industry standard protocol.

8. The process fluid pressure transmitter of claim 1, wherein the protocol is a 4-20 mA protocol.

9. The process fluid pressure transmitter of claim 1, wherein the protocol is a digital/analog hybrid protocol.

10. The process fluid pressure transmitter of claim 9, wherein the process fluid pressure is provided as a 4-20 mA signal, and wherein the indication related to the at least one stored parameter is communicated digitally over the process communication loop.

11. The process fluid pressure transmitter of claim 7, wherein the process fluid pressure and the indication related to the at least one stored parameter are communicated digitally over the process communication loop.

12. A method of operating a process fluid pressure transmitter, the method comprising:

coupling a pressure sensor to a source of process fluid;

repeatedly measuring process fluid pressure using the pressure sensor and communicating a signal related to each measurement over a process communication loop;

detecting a process fluid pressure transient using the pressure sensor;

storing at least one parameter related to the pressure transient in the process fluid pressure transmitter; and

providing an indication related to the at least one parameter.

13. The method of claim 12, wherein the indication is provided by causing the process fluid pressure transmitter to communicate over the process communication loop.

14. The method of claim 12, wherein the indication is provided by causing the process fluid pressure transmitter to communicate with a handheld field maintenance device coupled to the process fluid pressure transmitter.

15. The method of claim 12, wherein detecting the process fluid pressure transient includes comparing a process fluid pressure measurement with a user-provided pressure threshold.

16. The method of claim 15, wherein the user-provided pressure threshold is a maximum pressure threshold.

17. The method of claim 15, wherein the user-provided pressure threshold is a minimum pressure threshold.

18. The method of claim 12, wherein storing at least one parameter related to the pressure transient includes storing a value indicative of a time at which the transient was detected.

19. The method of claim 12, wherein storing at least one parameter related to the pressure transient includes storing a value indicative of a maximum pressure measured during the transient.

20. The method of claim 12, wherein storing at least one parameter related to the pressure transient includes storing a value indicative of total time spent beyond a user-provided pressure threshold.

21. The method of claim 12, wherein storing at least one parameter related to the pressure transient includes storing a value indicative of a number of transients detected.

22. The method of claim 12, wherein communicating a signal related to each measurement occurs at a first rate, and measuring process fluid pressure occurs at a second rate higher than the first rate.

23. The method of claim 22, wherein storing a parameter related to the pressure transient includes storing at least one pressure measurement value measured during the transient at the second rate.

24. The method of claim 23, and further comprising storing a time-stamp for each pressure measurement value measured during the pressure transient, at the second rate.