Source: https://patents.google.com/patent/US8452255B2/en
Timestamp: 2019-04-22 22:54:15
Document Index: 617683429

Matched Legal Cases: ['application No. 06774208', 'Application No. 06774208', 'application No. 9', 'application No. 2008', 'application No. 200680015575', 'application No. 2602758', 'application No. 2008103014', 'application No. 06774208', 'application No. 06774208', 'Application No. 200680015575']

US8452255B2 - Field device with dynamically adjustable power consumption radio frequency communication - Google Patents
US8452255B2
US8452255B2 US11/475,726 US47572606A US8452255B2 US 8452255 B2 US8452255 B2 US 8452255B2 US 47572606 A US47572606 A US 47572606A US 8452255 B2 US8452255 B2 US 8452255B2
US11/475,726
US20060290328A1 (en
2006-06-27 Application filed by Rosemount Inc filed Critical Rosemount Inc
2006-06-27 Priority to US11/475,726 priority patent/US8452255B2/en
2006-08-23 Assigned to ROSEMOUNT INC. reassignment ROSEMOUNT INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ORTH, KELLY M.
2006-12-28 Publication of US20060290328A1 publication Critical patent/US20060290328A1/en
2013-05-28 Publication of US8452255B2 publication Critical patent/US8452255B2/en
A field device for use in an industrial process control or monitoring system includes terminals configured to connect to a two-wire process control loop configured to carry data and to provide power. In one embodiment, RF circuitry in the field device is configured for radio frequency communication having variable power consumption. In another embodiment, the RF circuitry is coupled to the field device through a separate digital communication bus. A method of modulating the power of RF communication based upon a process communication signal is also provided.
The present application is based on and claims the benefit of U.S. provisional patent application Ser. No. 60/694,201, filed Jun. 27, 2005, the content of which is hereby incorporated by reference in its entirety.
FIG. 1 is a diagrammatic view of a process control and/or monitoring system in which embodiments of the present invention are particularly useful.
FIG. 2 is a simplified cutaway partially exploded view of a pressure transmitter.
FIG. 1 is a diagrammatic view of a process control and/or monitoring system 10 in which embodiments of the present invention are particularly useful. System 10 includes control room 12 that is coupled to field device 14 over a two-wire process control loop 16. Field device 14 is operably coupled to a process fluid container, illustrated diagrammatically as pipe 18, and is configured to determine a process variable relative to the process fluid within pipe 18 and convey information related to the process variable over process control loop 16.
The housing 62 includes endcap 70 and 72 which can be screwed into housing 62. Endcap 72 includes an RF transparent window 74 configured to align generally with an antenna 26 carried on wireless communication circuitry 22. When attached, endcaps 70 and 72 provide an intrinsically safe enclosure for circuitry within transmitter 14. The materials typically used in endcaps, for example, metal, are not transparent to RF signals. However, RF transparent window 74 allows RF signals to be sent from or received by antenna 26. One example of RF transparent material for use with windows 74 is glass, or the like. However, any appropriate material can be used. The window and housing configuration can help to meet intrinsic safety requirements and provide flame-proof or explosion-proof capabilities. Further, the cavity within housing 62 can be configured to provide a desired radiation pattern of RF signals generated by antenna 26. For example, it may be desirable to have the RF transmission be directional in some implementations, or omni-directional in others. In other implementations, cover 62 may be lengthened to provide an additional interior cavity for placement of wireless communication circuitry 22.
Wireless communication circuitry 22 interacts with external wireless devices via antenna 26. Depending upon the application, wireless communication circuitry 22 may be adapted to communicate in accordance with any suitable wireless communication protocol including, but not limited to: wireless networking technologies (such as IEEE 802.15.4 or IEEE 802.11b wireless access points and wireless networking devices built by Linksys of Irvine, Calif.), cellular or digital networking technologies (such as Microburst® by Aeris Communications Inc. of San Jose, Calif.), ultra wide band, free space optics, Global System for Mobile Communications (GSM), General Packet Radio Services (GPRS), Code Division Multiple Access (CDMA), spread spectrum technology, infrared communications techniques, SMS (Short Messaging Service/text messaging), or any other suitable wireless technology. Further, known data collision technology can be employed such that multiple units can coexist within wireless operating rage of one another. Such collision prevention can include using a number of different radio-frequency channels and/or spread spectrum technologies.
FIG. 4 is a diagrammatic view of a portion of field device circuitry 68 within field device 14 in accordance with an embodiment of the present invention. Field device circuitry 68 includes a digital modem 102 that allows field device 14 to communicate digitally over process control loop 16. In one embodiment, the digital communication is in accordance with the Highway Addressable Remote Transducer (HART®) protocol. Additionally, circuitry 68 includes shunt control module 104 that allows field device 14 to set the amount of current flowing between terminals 56H and 56L to a value between 4 and 20 mA in order to convey process variable information. Field device 14 preferably includes a pair of terminals 106, 108 through which digital communication bus 100 couples wireless communication circuitry 22. Field device 14 also preferably includes communication physical layer 110 that provides for communication in accordance with one of the digital communication bus options listed above. Additionally, field device 14 includes communication power limit module 112 that is operably coupled to high voltage rail 114 and to loop terminal 56L. Communication power limit module 112 is operably coupled to shunt control 104 such that power to the communication physical layer 110 is based upon current drawn by field device 14. As illustrated in FIG. 4, wireless communication circuitry 22 is coupled to terminals 106 and 108 via communication bus 100. As set forth above, wireless communication circuitry 22 can be disposed within field device 14, or located remotely therefrom.
The current required to make a single process measurement while keeping the 4-20 mA electronics and sensor circuitry within field device 14 functioning often requires up to 3.6 mA, which is the maximum limit allowed to meet NAMUR alarm levels. HART-based transmitters use +/−0.5 mA for signaling on the two wire loop, so only 3.1 mA of the 3.6 mA limit should be allocated for the operating current field device 14. In accordance with an embodiment of the present invention, field device 14 employs communication power limit module 112 to limit the electrical power provided for digital communications over digital communication bus 100, and accordingly through wireless communication circuitry 22. For example, when there is 4.0 mA of loop current, 0.7 mA of electrical energy is made available to digital communication bus 100. When there is 6.0 mA of loop current, 1.70 mA is made available to wireless communication circuitry 22 through digital communication bus 100.
As illustrated in FIG. 4, terminal 106 of digital communication bus 100 can be directly coupled to loop terminal 56L. In this embodiment, one of the wires of the two-wire 4-20 mA loop and the two-wire digital communication bus 100 are common. In this instance, the common line of digital communication bus 100 could in fact be coupled directly to the negative or low voltage line of the process communication loop and the interconnection between wireless communication circuitry 22 and field device 14 could be effected via a single wire coupled to terminal 108. In accordance with one embodiment of the present invention, digital communication bus 100 is a controller area network (CAN) bus and circuitry of field device 14 can be in accordance with that found in United States Patent Application Publication Serial Number 2004/0184517 A1, published Sep. 23, 2004 entitled TWO WIRE TRANSMITTER WITH ISOLATED CAN OUTPUT.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. As used herein, Radio Frequency (RF) can comprise electromagnetic transmissions of any frequency and is not limited to a particular group of frequencies, range of frequencies or any other limitation.
a plurality of electrical terminals coupled to conductors of a process control loop;
field device circuitry including a digital modem allowing the field device to communicate digitally over the process control loop;
a shunt control module operably coupled between the plurality of electrical terminals and configured to control amount of current flowing therethrough;
a communication power limit module operably coupled to the shunt control module to limit power provided to a digital communication bus based on the amount of current;
wherein the digital communication bus is operably coupled between the field device circuitry and wireless communication circuitry, the wireless communication circuitry being configured to operate at varying power levels based upon excess power available from the field device, wherein operation of the wireless communication circuitry is configured to be modified based upon the excess power available from the field device to dynamically change a power consumption rate of the wireless communication circuitry; and
wherein the wireless communication circuitry goes to a sleep mode for a period of time when excess power available from the field device is at a minimum.
4. The field device of claim 1, wherein the digital communication bus is a Controller Area Network bus.
5. The field device of claim 4, wherein the wireless communication circuitry is coupled to the field device through a single conductor.
6. The field device of claim 1, wherein the digital communication bus is a Local Interconnect Network (LIN) bus.
7. The field device of claim 1, wherein the digital communication bus is a Serial Communication Interface (SCI) bus.
8. The field device of claim 1, wherein the digital communication bus is a Serial Peripheral Interface (SPI) bus.
9. The field device of claim 1, wherein the digital communication bus is an I2C bus.
10. The field device of claim 1, and further comprising an energy storage device.
11. The field device of claim 1, wherein the field device is a process variable transmitter.
12. The field device of claim 1, wherein the wireless communication circuitry communication rate is proportional to the amount of current flowing through the shunt control module.
13. The field device of claim 1, wherein the wireless communication circuitry communication rate is a function of excess power available from the field device.
14. The field device of claim 13, wherein the wireless communication circuitry communication rate is proportional to the excess power.
15. The field device of claim 1, wherein the amount of current flowing through the plurality of terminals, and determined by the shunt control module, is utilized to power the field device.
US11/475,726 2005-06-27 2006-06-27 Field device with dynamically adjustable power consumption radio frequency communication Active 2029-12-31 US8452255B2 (en)
US11/475,726 US8452255B2 (en) 2005-06-27 2006-06-27 Field device with dynamically adjustable power consumption radio frequency communication
US20060290328A1 US20060290328A1 (en) 2006-12-28
US8452255B2 true US8452255B2 (en) 2013-05-28
US11/475,726 Active 2029-12-31 US8452255B2 (en) 2005-06-27 2006-06-27 Field device with dynamically adjustable power consumption radio frequency communication
CN106292460B (en) * 2016-09-30 2018-11-23 广州三业科技有限公司 An internal combustion engine power pack intelligent control system and control method
US20020005713A1 (en) * 2000-07-17 2002-01-17 Endress + Hauser Gmbh + Co. Measuring device for measuring a process variable
Decision to Refuse from a corresponding European patent application No. 06774208.0 dated Apr. 2, 2012.
First Communication issued by the European Patent Office in German Application No. 06774208.0.
First Examination Report from the related Indian patent application No. 9/MUMNP/2008 dated Jan. 3, 2012. 1 page.
First Office Action (Notification of Reasons for Rejection) for Japanese patent application No. 2008-518521 dated Aug. 24, 2010.
Fourth Office Action for Chinese patent application No. 200680015575.4 dated Jun. 9, 2011.
Office Action from Russian Patent Office in Russian U.S. Appl. No. 2006145434.
Office Action from the corresponding Canadian patent application No. 2602758 dated Oct. 10, 2012. 5 pages.
Official Action for Russian patent application No. 2008103014, filed Jun. 27, 2006.
Provision of the Minutes from the corresponding European patent application No. 06774208.0 dated Apr. 2, 2012.
Summons to attend Oral Proceedings for corresponding European patent application No. 06774208.0 dated Nov. 7, 2011.
Third Office Action for Chinese Patent Application No. 200680015575.4 dated May 11, 2010.
WO2007002769A1 (en) 2007-01-04
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ORTH, KELLY M.;REEL/FRAME:018205/0792