Field-mounted process device with programmable digital/analog interface

• US 20050195093A1
• Filed: 03/02/2005
• Published: 09/08/2005
• Est. Priority Date: 05/12/2000
• Status: Active Grant

• Current Assignee: Rosemount Incorporated (Emerson Electric Company)
• Original Assignee: Rosemount Incorporated (Emerson Electric Company)
• Inventors: Karschnia, Robert J., Peluso, Marcos
• Granted Patent: US 7,228,186 B2
• Time in Patent Office: Days
• US Class Current: 340/693.1
• CPC Class Codes: G05B 19/054 Input/output
• CPC Class Codes: G05B 2219/1157 I-O used either as input or as output
• CPC Class Codes: G05B 2219/1163 Multiplexer for analog signals
• CPC Class Codes: G05B 2219/14144 Galvanic isolation
• CPC Class Codes: G05B 2219/15091 Power and data bus
• CPC Class Codes: G05B 2219/25188 Superposition high frequency data signal on power lines, current carrier

Abstract

Embodiments of the present invention generally provide a field-mountable process device that receives digital information from one or more process devices, and provides an associated analog output. Embodiments of the present invention include providing a wireless interface to the field-mounted process device such that configuration and/or diagnostic information can be communicated between the field-mounted process device and one or more additional devices. In some embodiments, the field-mounted process device can be completely powered by the digital process communication loop to which it is coupled. Finally, embodiments of the present invention also include generating and storing within the field-mounted process device a mapping between one or more field devices communicating in accordance with a digital process communication protocol and an analog output of the field-mounted process device.

Claims

1. A field-mountable process device comprising:

a loop communicator configured to couple to a process communication loop and communicate digitally over the loop;

memory configured to store a map relating a first digital parameter relative to a first digital process device coupled to the process communication loop to a first analog module and a second digital parameter to a second analog module;

a controller coupled to the loop communicator and configured to convert between the first parameter and first analog signal information and to convert between the second digital parameter and second analog signal information;

a first analog module operably coupled to the controller and configured to convey a first analog signal related to the first analog signal information; and

a second analog module operably coupled to the controller and configured to convey a second analog signal related to the second analog signal information.

2. The device of claim 1, wherein the first analog module is an analog output module.

3. The device of claim 2, wherein the first analog module includes a HART digital communication chip.

4. The device of claim 2, wherein the second analog module is an analog output module.

5. The device of claim 2, wherein the second analog module is an analog input module.

6. The device of claim 1, wherein the first and second analog modules are analog input modules.

7. The device of claim 1, and further comprising a power module configured to coupled to the process communication loop and wholly power the device with power received from the loop.

8. The device of claim 1, wherein the loop communicator is a FOUNDATION Fieldbus communicator.

9. The device of claim 1, and further comprising a wireless communication module coupled to the controller.

10. The device of claim 9, wherein the device is configurable through the wireless communication module.

11. The device of claim 10, wherein the first process device provides additional digital information through the loop communicator, and wherein the controller causes the wireless communication module to transmit based on the additional digital information.

12. The device of claim 1, wherein the map is changeable.

13. The device of claim 12, wherein the map is changeable via the wireless communication module.

14. The device of claim 1, wherein the first analog module relates a 4-20 mA analog signal to first analog signal information.

15. The device of claim 1, wherein the controller is further configured to perform an operation upon the first parameter.

16. The device of claim 15, wherein the additional operation is specified in the map.

17. The device of claim 1, wherein the controller relates performs a control function and generates a control output based on the control function.

18. The device of claim 17, wherein the control output is conveyed through the loop communicator.

19. The device of claim 1, wherein the second digital parameter relates to a second digital process device coupled to the process communication loop.

20. A computer readable medium within a field-mountable process device, the computer readable medium comprising:

a first relationship relating a first digital process device with a first analog module of the field-mountable process device; and

a second relationship relating a digital process device with a second analog module of the field-mountable process device.

21. A process control system comprising:

a distributed control system having at least one analog communication channel;

a field-mountable process device having an analog module coupled to the at one analog communication channel of the distributed control system, and having a loop communicator coupled to a digital process communication loop; and

at least one process device coupled to the digital process communication loop; and

wherein the field-mountable process device converts between analog signals conveyed along the at least one analog channel, and digital signals conveyed through the loop communicator to or from the at least one process device.