Process variable measurement and local display with multiple ranges

Patent metadata

Field	Value
Publication number	US-9897505-B2
Application number	US-201514751754-A
Country	US
Kind code	B2
Filing date	Jun 26, 2015
Priority date	Jun 26, 2015
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

A process variable indicator is provided. The process variable indicator includes a process variable sensor having an electrical characteristic that varies with the process variable. Measurement circuitry is coupled to the process variable sensor and is configured to provide an indication relative to the electrical characteristic. A processor is coupled to the measurement circuitry and is configured to compute a process variable based on the indication and determine, among a plurality of ranges, which range the process variable is within. The processor generates a local visual output based on the process variable and the determined range. A method of visually indicating a process variable is also provided.

First claim

What is claimed is:

1. A process variable indicator comprising:
a process variable sensor having an electrical characteristic that varies with the process variable;
measurement circuitry coupled to the process variable sensor and configured to provide an indication relative to the electrical characteristic;
a visual output interface with a plurality of numerical indicators comprising a first range and a second range, wherein the first range comprises a first interval between numerical indicators, the second range comprises a second interval between numerical indicators, and the first and second intervals are different; and
a processor coupled to the measurement circuitry, the processor being configured to compute a process variable based on the indication and determine; among a plurality of ranges, that the process variable is within the first range and generate a local visual output on the visual output interface of the process variable within the first range.

2. The process variable indicator of claim 1 , and further comprising a wireless communication module coupled to the processor to communicate with a remote device wirelessly.

3. The process variable indicator of claim 2 , wherein generating the local visual output includes interacting with an actuator to cause movement of a physical indicator.

4. The process variable indicator of claim 3 , and further comprising a pre-printed face disposed proximate the physical indicator, the pre-printed face having indicia indicative of the first and second ranges.

5. The process variable indicator of claim 4 , wherein the processor causes the physical indicator to move a first amount relative to a process variable difference in the first range, and move a second amount, different than the first amount, for the process variable difference in the second range.

6. The process variable indicator of claim 5 , wherein the physical indicator comprises a needle.

7. The process variable indicator of claim 6 , wherein the needle is rotatable to indicate the process variable.

8. The process variable indicator of claim 3 , wherein the actuator is a stepper motor.

9. The process variable indicator of claim 2 , and further comprising at least one auxiliary output configured to indicate a condition different than the process variable.

10. The process variable indicator of claim 9 , wherein the condition is a low-battery condition.

11. The process variable indicator of claim 9 , wherein the condition is indicative of the occurrence of an excessive process variable.

12. The process variable indicator of claim 1 , wherein the process variable is process fluid pressure.

13. The process variable indicator of claim 12 , wherein the process variable sensor is a strain-gauge process fluid pressure sensor.

14. The process variable indicator of claim I, wherein the process variable is temperature.

15. The process variable indicator of claim 1 , wherein the processor is configured to access memory containing information indicative of the first and second ranges.

16. The process variable indicator of claim 15 , wherein the memory includes a plurality of thresholds relative to each range boundary.

17. The process variable indicator of claim 1 , and further comprising an internal battery configured to power the process variable indicator.

18. The process variable indicator of claim 1 , and further comprising a graphical display device coupled to the processor and configured to provide the local visual output.

19. A method of visually indicating a process variable, the method comprising:
obtaining process variable information from measurement circuitry;
determining a current range containing the process variable, among a plurality of ranges; and
causing an actuator to move a physical indicator, on a visual interface associated with the measurement circuitry, based on the process variable information and the current range containing the process variable, wherein the visual interface comprises the plurality of ranges, and wherein causing the actuator to move the physical indicator comprises the physical indicator moving into the current range on the visual interface.

20. The method of claim 19 , wherein causing the actuator to move a physical indicator includes energizing a stepper motor to cause movement of the physical indicator.

21. The method of claim 19 , wherein Obtaining process variable information includes measuring an electrical characteristic of a process variable sensor.

22. The method of claim 19 , and further comprising wirelessly communicating the process variable information.

Assignees

• Rosemount Inc

Inventors

• Hedtke Robert C

Classifications

• G01L19/16

  Dials; Mounting of dials · CPC title

• G01K1/028

  arrangements for numerical indication · CPC title

• G01L19/10 Primary

  mechanical · CPC title

• G01L19/086

  for remote indication · CPC title

• G01L19/083

  electrical · CPC title