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Contents
1. S 071 41 39IA3d 91315 10 NOILIGNOD 3NIA313Q 081 US 2014 0236318 A1 Aug 21 2014 Sheet 4 of 5 Patent Application Publication NOILIQNOO q34IS3dNn 40 VIVO NOILVOIGNI xovgav3d JSN 319A908H9VIN 7 Iwaw gt za i8 9ST OST MF eS OVI US 2014 0236318 A1 Aug 21 2014 Sheet 5 of 5 Patent Application Publication 081 JALIY CBIN JHL Ild 3141 DIR 5 115 806 039539094 SI YOOTE YIINASNYYL Yovaqvau JHL NI JHL ee G31093X3 SI 3004 01 OL 31VIS 5 11 39018 1081409 29018 SH39n SNVHL JHL NI 1 325354 SI 31VIS LIAW4 lVHL 9NISS390Hd SI 32018 100 JGOW 500 01 S3HOLIMS 91 3HL ONILISS IHL NO 5NIIN3d3Q 1 104135 3115 31VILINI S11V1S 80 NOILISOd Novaav3d AL vno 39018 YFONGSNVYL FHL 804 LNIOd 1009 1 04 135 155 3HL SALVINOWO 3Q0W 10 29 72 SI 32018 LNO 0009 1 104 138 1 891 991 2 00 834 d3HH33SNVMl SI VlvO NY 300 10 05 2 NI SI 4001 3 1 1 3HL MOTIOS OL l MOTIV LON 300 NOILIGNOD AYVHOdWSL V 5193130 0018 W39nasNvul 3Hl JUV 5114100 Q310103X3 SI 39018 TOULNOD 19018 39018 2018 104110 1041802 WOMOVE 39018 39018 1084110 0912. sion DD revision and or update revision which may be used during commissioning or decommissioning by the commis sioning decommissioning system 25 In this way the field devices 34 36 38 and 40 may contribute control logic and other computer instructions towards the execution of pro cesses in the industrial process control system 10 0023 Inone example a placeholder may be created by the commissioning decommissioning system 25 The place holder may be an object stored in memory 16 that represents the field device 38 Accordingly a user may pre commission a system by creating one or more of the placeholder each of the placeholders representing the device 38 and then use the placeholder s during commissioning of the physical field device 38 The placeholder may include physical device PD tag manufacturer ID device type device revision DD revi sion and or update revision representative of the field device 38 The PD tag may include a device name useful in identi fying the device 38 Likewise the manufacturer ID may include information identifying the manufacturer of the device 34 The device type may be suitable for identifying the type of device e g valve sensor actuator while the device revision may be a version number indentifying the device version Likewise the DD revision may identify the DD version such as a DD file version included in the device 38 It should be appreciated that in another embodiment the de
3. following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings wherein 0008 FIG 1 is a schematic diagram of an embodiment of an industrial control system including an industrial control ler and a valve Aug 21 2014 0009 FIG 2 is a schematic diagram of an embodiment of an industrial controller and a pneumatic valve 0010 FIG 3 is a flowchart of an embodiment of a process suitable for detecting communicating and ameliorating an undesired condition in field devices 0011 FIG 4 is a timing diagram of an embodiment of an Output function block using a ReadBack facility to indicate an undesired condition during a macrocycle and 0012 FIG 5 is an information flow diagram showing embodiments of information being transferred between a control block output block and transducer block DETAILED DESCRIPTION OF THE INVENTION 0013 or more specific embodiments of the present invention will be described below In an effort to provide a concise description of these embodiments all features of an actual implementation may not be described in the specifica tion It should be appreciated that in the development of any such actual implementation as in any engineering or design project numerous implementation specific decisions must be made to achieve the developers specific goals such as com pliance with system related and busine
4. a standard fieldbus value to a value analog or digital that can be used by the transducer function block 162 In normal operation as described above the valve may move the actuator and the valve member to the desired position 0037 However in the case of an undesired condition the transducer function block 162 through the valve positioner may detect the condition and switch process block 174 the transducer block 162 to Out of Service or Manual mode In Out of Service mode the function block is inactive and the output of the function block maintains the last value or a failure action value In Manual mode the output of the func Aug 21 2014 tion block remains unchanged until a new value is set by an operator In this embodiment the valve positioner 116 moni tors the undesired condition i e insufficient supply air pres sure The valve positioner 116 and or other sensors and actuators can be used to monitor other multiple undesired conditions such as insufficient hydraulic pressure insuffi cient wind power or improper electric power e g incorrect frequency Also potential undesired conditions can be moni tored at the same time The transducer block 162 may then use its ReadBack facility to return data flow 176 a sub status of Initiate Fault State Once the output block 160 receives the Initiate Fault State sub status it may switch process block 178 the output function block 160 from Cascade mode into Out of Servi
5. control function block 158 The dis closed embodiments may instead use the sub status in the OUT parameter to inform the control function block 158 that an undesired condition is present In addition the output block 160 may return a status that indicates the limited SetPoint so that recovery may be bumpless 0039 Without the disclosed embodiments when the Out put function block 160 is assigned to a field device such as a valve the BKCAL OUT parameter may be used to commu nicate information such as actuator position In other words without the disclosed embodiments the OUT parameter may be used to communicate conditions affecting mode and status that are related to the hardware and or soft ware health of the field device using the ReadBack facility disclosed embodiments on the other hand use the Out put function block 160 that communicates undesired condi tions not included in the hardware and or software health of the field device such as the insufficient air pressure being supplied by the air supply 126 or other conditions related to systems external to the field device Thus the disclosed embodiments have adapted the OUT parameter to communicate conditions that previously were either not being communicated to the control strategy or were commu nicated using additional and or custom function blocks to communicate to the control strategy 08 2014 0236318 1 0040 Once sub s
6. for asynchronous communications e g alerts and or downloads by devices on a communications segment e g an segment 0017 The disclosed embodiments provide a system and method to provide field device feedback especially for those parameters not included in the health definitions of the Foun dation Fieldbus protocol In one embodiment by utilizing the ReadBack facility of Foundation Fieldbus function blocks the present techniques are able to detect and communicate an undesired fault condition and recovery from the fault condi tion to the industrial controller without the use of additional or custom function blocks and without the need for additional bandwidth within the macrocycle Furthermore because when a field device is not functioning as desired due to an undesired condition it may be very useful to take ameliora tive action as quickly as possible If the techniques described herein are enabled during commissioning the disclosed embodiments may be able to almost immediately switch to an OOS Out of Service Manual or Local Override Mode which signals to the industrial controller that the field device is not responding because a fault state is active The industrial controller can then take further actions based on feedback which may include information concerning undesired field device conditions e g low actuation air pressure low actua tion amperage sticky valve or foreign object in a valve 0018 Turning t
7. with reference to FIG 5 one embodiment utilizes a function block such as a transducer function block to determine whether the condition has to be reported If the condition is not an undesired condition the process 128 returns to block 130 and continues to monitor the condition e g insufficient air pressure or functioning properly of the field device If the condition of the field device is an undesired condition the process 128 puts block 134 the field device e g valve 38 into a fault state such as Aug 21 2014 Local Override Mode which immediately stops the field device from trying to follow the industrial controller s instructions 0031 Next the process 128 may add block 136 indica tion data of the undesired condition to the ReadBack Facility As will be described in more detail in reference to FIG 5 the ReadBack Facility may be part of an Output function block that allows for the Output function block to feedback a signal to a control block for example through a sub status category This may be implemented using the BKCAL OUT and BKCAL IN parameters Specifically Block 136 may be implemented by writing to the BKCAL OUT parameter on the Output function block The process 128 then uses the ReadBack facility to communicate block 138 the indication data to the industrial controller 30 which may be imple mented by reading the IN parameter on the control block Similarly if the undes
8. 08 2014 0236318 1 SYSTEMS AND METHODS FOR FIELD DEVICE FEEDBACK BACKGROUND OF THE INVENTION 0001 The subject matter disclosed herein relates to sys tems and methods for feedback of certain devices and more specifically in field devices 0002 Certain systems such as industrial control systems may include capabilities that enable the system to detect and correct undesired conditions within the system For example the Foundation Fieldbus protocol provides smart field devices with the ability to communicate conditions that are related to the hardware and or software health of the device to the control system s control strategy However when the undes ired condition is not part of the hardware or software the smart field device by itself may be unable to communicate the presence of the undesired condition This could include con ditions like insufficient air pressure to a pneumatic digital valve BRIEF DESCRIPTION OF THE INVENTION 0003 Certain embodiments commensurate in scope with the originally claimed invention are summarized below These embodiments are not intended to limit the scope of the claimed invention but rather these embodiments are intended only to provide a brief summary of possible forms of the invention Indeed the invention may encompass a variety of forms that may be similar to or different from the embodi ments set forth below 0004 In a first embodiment a system includes an indus trial controlle
9. 62 may be programmati cally used in certain control algorithms so that data computed by using oneor more function blocks may be used as inputs to other function blocks It should be appreciated that alterna tively all of the function blocks may be included in the same field device e g valve 38 and or in the controller 30 0036 To better illustrate the information flow the function blocks 158 160 and 162 can be described in relation to the pneumatic valve 38 in FIG 2 and may include Foundation Fieldbus capabilities The industrial controller 30 through the control function block 158 may implement a control strategy 164 to guide the functioning of the rest ofthe control system Alternatively the control function block 158 may be included in the field device 38 In some embodiments the control block 158 may be a proportional integral derivative PID control block 158 Following the control strategy 164 the control block 158 may begin by calculating process block 166 a desired valve position and passing data flow 168 the information to the output function block 160 for example as a first SetPoint Because the output function block 160 may be in Cascade Mode e g a mode that uses a master slave con figuration it may use the first SetPoint to decide the value process block 170 for a second SetPoint and pass data flow 172 the second SetPoint to the transducer function block 162 This second SetPoint may be used to translate
10. US 20140236318A1 19 United States a2 Patent Application Publication Pub No US 2014 0236318 A1 Esposito et al 43 Pub Date Aug 21 2014 54 71 72 73 21 22 SYSTEMS AND METHODS FOR FIELD DEVICE FEEDBACK Applicant GENERAL ELECTRIC COMPANY Schenectady NY US Inventors Sandro Esposito Katy US John Alexander Petzen Roanoke US Vladimir Dimitrov Kostadinov Sharon MA US Assignee GENERAL ELECTRIC COMPANY Schenectady NY US Appl No 13 772 233 Filed Feb 20 2013 25 DECOMMISSIONING A MES Lae ISIM a SCADA 1 65 HFBaje 142 ME UN At AL 56 0 Nus 82 34 Bu gg 96 64 98 90 Publication Classification 51 Int Cl G05B 11 01 2006 01 52 1 5 G05B 11 01 2013 01 USPE 700 79 700 287 57 ABSTRACT embodiments described herein include a system and a method In one embodiment a system includes an industrial controller configured to control a first field device The first field device includes an actuator and a positioner coupled to the actuator The positioner is configured to position the actuator The first field device is configured to detect an undesired condition and to communicate the undesired con ditionto the industrial controller by u
11. a gas turbine system a gas ification system a steam turbine system a wind turbine sys tem a water turbine system a power generation system or any combination thereof 12 A method comprising determining a state of a field device deriving a first indication of an undesired condition if the state includes an undesired condition then adding the first indication of the undesired condition to a ReadBack facility and communicating the first indication to a control block 13 The method of claim 12 wherein communicating the indication comprises using a Foundation Fieldbus communi cations protocol 14 The method of claim 13 comprising placing the field device in Manual Out of Servicer or Local Override mode 08 2014 0236318 1 15 The method of claim 12 wherein ReadBack facility comprises a Fault State Active sub status code category con figured to include an indication of the undesired condition 16 The method of claim 12 comprising deriving a second indication of a recovered condition if the state includes a recovered condition then adding the second indication of the recovered condition to the ReadBack facility and communicating the second indication to a control block 17 The method of claim 12 wherein the field device is included in an industrial control system comprising a gas turbine system a gasification system a steam turbine system a wind turbine system a water turbine system a power g
12. al integral derivative PID controller Accordingly the PID controller may be implemented by a PID function block The function blocks 41 may include computer instructions or computer logic executable by processor 32 The industrial controller 30 may communicate with a variety of field devices including but not limited to flow meters pH sensors temperature sensors vibration sensors clearance sensors e g measuring distances between a rotating component and a stationary component pressure sensors pumps actuators valves and the like In some embodiments the industrial controller 30 may be a Mark VIe controller system avail able from General Electric Co of Schenectady N Y includ ing a triple modular redundant TMR controller 30 having three cores e g S T suitable for redundant controller operations For example the R S and T cores may vote to determine control actions 0020 In the depicted embodiment the turbine system 34 the temperature sensor 36 the valve 38 and the pump 40 are communicatively connected to the industrial controller 30 by using linking devices 44 and 46 suitable for interfacing between an I O network 48 and an network 50 For example the linking devices 44 and 46 may include the FG 100 linking device available from Softing AG of Haar Germany As depicted the linking devices 44 and 46 may include processors 52 and 54 respectively useful in execut ing computer instructions an
13. and the position of the valve member may be changed as desired 0026 An undesired condition may arise when the posi tioner 116 is unable to receive sufficient air pressure from the air supply 126 resulting in the positioner 116 having diffi culty moving the actuator 118 to the desired position In some cases the industrial controller 30 may not be aware of the undesired condition e g low air supply pressure because the undesired condition is external to the valve 38 and thus not included in hardware and or software health definitions of the valve 38 To account for this the user may extend the control strategy and execute additional function blocks to collect the information however this may slow down the control pro cess and reduce the quality of control If the undesired con dition is unaccounted for the controller 30 may continue following the control strategy and operate as if the valve is in the correct position This can cause undesired behavior in the system 10 For example if the controller 30 derives that the valve 38 is more open than it actually is this could result in a back up in pipe 123 In addition when the controller 32 is a PID controller ifthe controller 32 is unaware that the valve 38 is unable to move to follow the setpoint the controller 32 may 08 2014 0236318 1 continue to integrate causing error to build up control output value which may make the recovery process difficult Thus undesire
14. ce Manual or Local Override mode In the Foundation Fieldbus protocol these modes are part of output function blocks including the Analog Output AO the Digi tal Output DO or a combination thereof The new mode may stop the output block 160 from using the first SetPoint and may instead set the second SetPoint to a specified value Thus the output block 160 may stop calculating the second SetPoint 0038 The output block 160 may the use the ReadBack facility to return data flow 180 a sub status of Failed State Active to notify the control function block 158 of the undes ired condition in the field device Additionally or alterna tively output function block 160 may return a sub status of NotInvited or NotSelected The ReadBack facility may be implemented by the BKCAL parameter on the output function block 160 The BKCAL OUT parameter is used to communicate a value and a status including sub status that may be required by the BKCAL IN of another function block The BKCAL OUT parameter may be communica tively coupled to the BKCAL IN parameter on the control function block 158 The two function blocks may communi cate through a publish subscribe protocol which allows for the communications to be fast and deterministic in schedule The BKCAL OUT parameter may be used to help provide smooth mode transfer when the mode on the output function block 160 15 changed by providing a value and status includ ing sub status to the
15. d conditions may be detected and communi cated back to the industrial controller 30 as quickly as pos sible to for example more properly actuate the valve 38 or use a backup valve 0027 The techniques described below may be used in other field devices 38 including different types of valves e g electric electro pneumatic hydraulic and electro hydraulic valves flow meters pH sensors temperature sensors vibra tion sensors clearance sensors e g measuring distances between a rotating component and a stationary component pressure sensors pumps and actuators Similar to insufficient air pressure in the pneumatic valve 38 undesired conditions may not be included in the hardware and or software defini tions of the field device For example an electric valve that relies on electricity to activate the valve may suffer from an undesired condition such as insufficient power or incorrect frequency of the input from an external power source Simi larly a wind pump that relies on wind power to supply energy to the pump may suffer from an undesired condition such as insufficient wind flow Accordingly FIG 3 describes one technique to communicate the undesired conditions to the controller 30 0028 FIG 3 is a flowchart of an embodiment of a process 128 suitable for detecting communicating and ameliorating an undesired condition using an embodiment of the field device feedback utilizing for example a ReadBack facility As descr
16. d may also include memory 56 and 58 useful in storing computer instructions and other data In some embodiments the I O network 48 may be a 100 Megabit MB high speed Ethernet HSE network and the network 50 may be a 31 25 kilobit second network Accordingly data transmitted and received through the I O network 48 may in turn be transmitted and received by the H1 network 50 That is the linking devices 44 and 46 may act as bridges between the I O network 48 and the H1 network 50 For example higher speed data on the I O network 48 may be buffered and then transmitted at suitable speed on the network 50 Accordingly a variety of field devices may be linked to the industrial controller 30 and to the computer 12 For example the field devices 34 36 38 and 40 may include industrial devices such as Fieldbus Foundation devices that include support for the Foundation H1 bi directional commu nications protocol The field devices 34 36 38 and 40 may also include support for other communication protocols such 08 2014 0236318 1 as those found in the Communications Foundation HCF protocol and the Profibus Nutzer Organization e V PNO protocol 0021 Each of the linking devices 44 and 46 may include oneor more segment ports 60 and 62 useful in segmenting the network 50 For example the linking device 44 may use the segment port 60 to communicatively couple with the devices 34 and 36 while the linking d
17. echanical energy to move the valve member to the desired position The valve member may move in either a linear or rotary manner In a linear valve the throughput of the valve may be changed by moving the valve member linearly in the valve Ina rotary valve the throughput of the valve may be changed by rotating the valve member in the valve 0025 The actuator 118 may be different types including wheel and axle pneumatic hydraulic solenoid screw and manual For example in a pneumatic valve 38 the positioner 116 may increase or decrease the air supplied to the actuator 118 based on the desired valve position Accordingly the air supplied to the actuator 118 may move the valve member to the desire valve position More specifically in a functioning pneumatic valve 38 the industrial controller 30 may send control actions through conduit 120 according to a control strategy for the control system to the positioner 116 which includes a desired valve position The positioner 116 is then able to determine the current position of the actuator 118 for example by using conduit 122 and determine the air pressure to supply to the actuator 118 to move the valve member to the desired position The positioner 16 may the supply the deter mined amount of air from the air supply 126 In the depicted embodiment the air supply 126 is located external to the pneumatic valve 38 The air may then be applied to the actua tor 118 through fluid conduit 124
18. en eration system or any combination thereof 18 non transitory tangible computer readable medium storing a plurality of instructions executable by a processor of an electronic device the instructions comprising instructions to determine a state of a field device instructions to derive an indication of an undesired condi tion if the state includes an undesired condition then instructions to add the indication of the undesired condi tion to a ReadBack facility and instructions to communicate the indication to a control block 19 The medium of claim 18 wherein communicating the indication comprises using a Foundation Fieldbus communi cations protocol 20 The medium of claim 18 wherein the ReadBack facil ity comprises a Fault State Active sub status code category configured to include an indication of the undesired condi tion Aug 21 2014
19. evice 46 may use the segment port 62 to communicatively couple with the devices 38 and 40 Distributing the input output between the field devices 34 36 38 and 40 by using for example the segment ports 60 and 62 may enable a physical separation useful in maintaining fault tolerance redundancy and improving com munications time 0022 Each field device 34 36 38 and 40 may include a respective device description DD file such as the depicted DD files 64 66 68 and 70 The DD files 64 66 68 and 70 may be written in a device description language DDL such as the DDL defined in the International Electrotechnical Commission IEC 61804 standard In some embodiments the files 64 66 68 and 70 are tokenized binary files That is the DD files 64 66 68 and 70 may include data formatted in a tokenized binary format useful in reducing the size of the DD files 64 66 68 and 70 The DD files 64 66 68 and 70 may each include one or more function blocks 72 74 76 and 78 The function blocks 72 74 76 and 78 may include computer instructions or computer logic executable by pro cessors 80 82 84 and 86 Indeed the function blocks 72 74 76 and 78 may be instantiated into memory 88 90 92 94 and then executed by the processors 80 82 84 and 86 respectively Each ofthe DD files 64 66 68 and 70 may also include device information 96 98 100 and 102 such as manufacturer identification ID device type device revi
20. evices will have the capability to transmit feedback to the industrial controller issues that relate to the hardware and or software of the device on a periodic basis For example the Foundation Fieldbus protocol Inter national Electrotechnical Commission IEC 61804 is a two way communication system which interconnects various fieldbus devices such as sensors pumps valves industrial controllers and the like via a local area network LAN However the Foundation Fieldbus protocol does not include the same feedback ability for communicating undesired con ditions such as insufficient air pressure because the field device itself 15 not defective or faulted The insufficient air pressure may be attributed to an air supply external to the field device Other undesired conditions may include low actua tion amperage a sticky valve or a foreign object in a valve It may be plausible to implement a solution that uses additional function blocks to specifically monitor parameters like sup ply air pressure However the use of the additional function 08 2014 0236318 1 blocks requires additional processing power and bandwidth which may result in slower execution In some cases the host may poll for an undesired condition during a specified time often close to 30 or more seconds A macrocycle as dis cussed herein may refer to a cycle of scheduled function block execution scheduled communication time and a por tion of time reserved
21. hat occur to those skilled in the art Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language ofthe claims or if they include equivalent structural elements with insubstantial differences from the literal language ofthe claims 1 A system comprising an industrial controller configured to control a first field device Aug 21 2014 the first field device comprising an actuator a positioner coupled to the actuator and configured to position the actuator wherein the first field device is configured to detect an undesired condition and to communicate the undesired condition to the industrial controller by using a ReadBack facility of the first field device 2 The system of claim 1 wherein the first field device comprises a Foundation Fieldbus first field device configured to communicate with the industrial controller 3 The system of claim 2 wherein the Fieldbus Foundation first field device comprises a Foundation Fieldbus digital output DO function block a Foundation Fieldbus analog output AO or a combination thereof having the ReadBack facility 4 The system of claim 3 wherein the ReadBack facility comprises a Fault State Active sub status code category con figured to indicate the undesired condition 5 The system of claim 4 wherein the Fault State Active sub status code category is configured to be transmitted by publi
22. ibed above the field device may be commissioned by the commissioning decommissioning system 25 using a placeholder representative of the field device with the Read Back facility 0029 The process 128 may be implemented by using computer instructions stored in a non transitory computer readable medium such as the memory of a computer server laptop tablet cell phone mobile device or similar process ing or computing device The process 128 may begin by determining block 130 the condition of the field device 38 The condition of the field device 38 may be determined by various sensors in the field device 38 For example in the pneumatic valve 38 described in FIG 2 a condition of insuf ficient air pressure may be determined when a sensor in the air supply 116 detects insufficient pneumatic pressure being supplied Similarly another condition of foreign object present may be determined when a sensor located within the pipe 123 detects a foreign object within the pipe Other sen sors in the pneumatic device 38 may be used to determine other conditions such as valve not moving properly when the vale is jamming sticking or generally not responding properly condition of functioning properly may be deter mined when none of the sensors in the field device 38 detect an issue 0030 The process 128 then determines whether decision block 132 the condition is an undesired condition As will be described in more detail
23. ing the safety of the system 10 0034 Referring back to FIG 3 once the industrial con troller 30 receives the indication data the process 128 may determine block 142 at least one action to take in order to ameliorate or eliminate the undesired condition For example a backup valve may be used as an alternative to the malfunc tioning valve fluids may be transferred via an alternate pipe alarms may be set other systems may be notified and so on Finally the process 128 may execute 144 the action to ameliorate or eliminate the undesired condition As will be described in further detail in FIG 5 block 142 and 144 may be executed in the control block 0035 FIG 5 is an information diagram showing embodi ments of an information flow between a control function block 158 output function block 160 and transducer function block 162 in an exemplary embodiment The information diagram may be executed in one macrocycle or one control loop In some embodiments the control block 158 is executed using the industrial controller 30 of FIG 1 The industrial controller 30 is communicatively coupled to a first field device such as the valve 30 having the output block 160 and the transducer block 162 In the depicted embodiment the output block 160 and the control block 158 may communicate through one or more fieldbus publisher subscriber periodic communication connections as described above The output block 160 and the transducer block 1
24. ion of the macro cycle 146 one or more function blocks may execute at desired time slots As an example these function blocks may include Alarm Detection Function Blocks Analog Input Function Blocks Calculation Logic Function Blocks Filter Function Blocks and Arithmetic Function Blocks In the depicted embodiment the macrocycle 146 begins by executing func tion block 1 FB1 at time slot 148 followed by function block 2 FB2 at time slot 150 and so on When the macrocycle reaches the Output function block e g Analog Output AO or the Digital Output DO time slot 152 and an undesired condition is detected the Output function block may use the ReadBack facility to indicate block 154 the undesired con dition The macrocycle 146 may continue executing function blocks until reaching function block FBN time slot 156 Then the macrocycle 146 may repeat execution of function blocks for example by starting over with FB1 at time slot 148 By using the ReadBack facility the techniques described herein provide for deterministic execution of processes asso ciated with the controller 30 In other words control may be provided at substantially the same execution time even when undesired conditions are detected and control actions may be 08 2014 0236318 1 modified correlative with detected conditions Accord ingly the undesired conditions may be overcome by control actions or notifications may be provided thus improv
25. ired condition disappears the process 128 may then use the ReadBack facility to commu nicate a status of good so that the control algorithm may resume normal control operations 0032 one embodiment the blocks 130 134 136 and 138 may execute within a Time N 140 In some embodiments Time 140 is 1 2 macrocycles where a macrocycle refers to a cycle of scheduled function block execution scheduled communication time and a portion oftime reserved for asyn chronous communications In other words a macrocycle may be one control loop execution The Foundation Fieldbus pro tocol may allow macrocycles to be configured at between 10 250 100 500 250 1000 750 3000 or more milliseconds Thus by using the ReadBack techniques disclosed herein the Time N 140 may be as fast as 10 250 milliseconds or 250 3000 milliseconds The techniques herein enable a quicker notification of an undesired condition because it enables the undesired condition to be reported in 1 2 loop executions as compared to additional custom function blocks which may poll for the undesired condition after a specified time such as 30 seconds A more detailed explanation ofthe functioning of the ReadBack facility within a macrocycle is described in FIG 4 0033 FIG 41 diagram ofan embodiment ofa macrocycle 146 including an Output function block Analog or Digital 152 having ReadBack facility for indicating the presence of an undesired condition During the execut
26. n when the function blocks are in a cascade loop the control function block 158 may act similarly to the Output function block 160 and use its ReadBack facility to notify another control function block 158 of the undesired condition In other words the presence of the undesired condition may be passed between coupled control function blocks 158 through the ReadBack facility Accordingly similar to the techniques described above the time to communicate the presence of an undesired condition between the control function blocks 158 may be one macro cycle 146 0043 Technical effects of the described embodiments include efficiently enabling the field device 38 to communi cate the presence of an undesired condition such as insuffi cient pneumatic pressure to a controller 30 In particular the field device 38 may be able to utilize the feedback function specifically the ReadBack facility on the Output function block 160 In other words the field device 38 may be able to communicate the presence of the undesired condition using the existing function blocks without additional bandwidth 0044 This written description uses examples to disclose the invention including the best mode and also to enable any person skilled in the art to practice the invention including making and using any devices or systems and performing any incorporated methods The patentable scope of the invention is defined by the claims and may include other examples t
27. nd or commissioning decommis sioning system 25 may be stored as executable code instruc tions on non transitory tangible computer readable media such as the memory 16 of the computer 12 For example the computer 12 may host the ToolboxST and or ControlST software available from General Electric Company of Schenectady N Y Aug 21 2014 0019 Further the computer system 12 is communica tively connected to a plant data highway 26 suitable for enabling communication between the depicted computer 12 and other computers 12 in the plant Indeed the industrial control system 10 may include multiple computer systems 12 interconnected through the plant data highway 26 The com puter system 12 may be further communicatively connected to a unit data highway 28 suitable for communicatively cou pling the computer system 12 to an industrial controller 30 industrial controller 30 may include a processor 32 and memory 42 suitable for executing a control strategy useful in automating a variety of plant equipment such as a turbine system 34 e g gas turbine steam turbine water turbine wind turbine etc a power generation system a heat recovery steam generator HRSG a gas treatment system a tempera ture sensor 36 a valve 38 and a pump 40 This may be implemented through the use of one more function blocks 41 executable by the industrial controller 30 In some embodi ments the industrial controller 30 may be a proportion
28. o FIG 1 an embodiment of an industrial control system 10 is depicted The industrial control system 10 may include a computer system 12 suitable for executing a variety of field device configuration and monitoring appli cations and for providing an operator interface through which an engineer or technician may monitor the components of the control system 10 Accordingly the computer 12 includes a processor 14 that may be used in processing com puter instructions and a memory 16 that may be used to store computer instructions and other data The computer system 12 may include any type of computing device or a combina tionofcomputing devices suitable for running software appli cations such as a laptop a workstation a tablet computer or a handheld portable device e g personal digital assistant or cell phone Indeed the computer system 12 may include any ofa variety ofhardware and or operating system platforms In accordance with one embodiment the computer 12 may host an industrial control software such as a human machine interface HMI software 18 a manufacturing execution sys tem MES 20 a distributed control system DCS 22 and or a supervisor control and data acquisition SCADA system 24 A commissioning decommissioning system 25 may be included in the HMI 18 MES 20 DCS 22 and or SCADA 24 and used to commission and or decommission certain devices as described in more detail below The HMI 18 MES 20 DCS 22 SCADA 24 a
29. r configured to control a first field device The first field device includes an actuator and a positioner coupled to the actuator The positioner is configured to position the actuator The first field device is configured to detect an undesired condition and to communicate the undesired con dition to the industrial controller by using a ReadBack facility of the first field device 0005 second embodiment a method includes deter mining a state of a field device And if the state includes an undesired condition then deriving an indication of an undes ired condition and adding the indication of the undesired condition to a ReadBack facility The method further includes communicating the indication to a control block 0006 In a third embodiment a non transitory tangible computer readable medium storing a plurality of instructions executable by a processor ofan electronic device the instruc tions include instructions to determine a state ofa field device If the state includes an undesired condition the instructions also include instructions to derive an indication ofthe undes ired condition The instructions further include instructions to add the indication of the undesired condition to a ReadBack facility and instructions to communicate the indication to a control block BRIEF DESCRIPTION OF THE DRAWINGS 0007 These other features aspects and advantages of the present invention will become better understood when the
30. sh subscribe protocol from the BKCAL OUT param eter of the Foundation Fieldbus digital output DO function block the Foundation Fieldbus analog output AO or a combination thereof 6 The system of claim 3 wherein the first field device is configured to set the Foundation Fieldbus digital output DO function block the Foundation Fieldbus analog output AO oracombination thereofto a Manual Out of Service or Local Override mode 7 The system of claim 1 wherein the first field device comprises a valve having an inlet and an outlet and wherein the actuator is configured to enable a flow between the inlet and the outlet 8 The system of claim 1 wherein positioner comprises a linear positioner configured to transform linear motion into an actuator position a rotary positioner configured to trans form rotary motion into the actuator position or a combina tion thereof 9 The system of claim 1 wherein the industrial controller is configured to control a second field device based on the undesired condition and the second field device is configured to provide redundant operations for the first field device 10 The system of claim 1 comprising a commissioning system having a placeholder representative of the first field device wherein the commissioning system is configured to use the placeholder to commission the first field device 11 The system of claim 1 wherein the system is an indus trial control system comprising
31. sing a ReadBack facility of the first field device PLANT DATA HIGHWAY 26 0 IM UNIT DATA HIGHWAY 28 30 1 0 NET HSE 100MB ETHERNET 48 Time vi d g i NETWORK 50 US 2014 0236318 A1 Aug 21 2014 Sheet 1 of 5 Patent Application Publication I 5 4 UNEEN og TER o 06 E TEn NEZER 88 5 5 Spl eT HELLO 05 7 YYOMLIN TH AW 09 7 09 99 F 2 LA 9 42 R UD 8y 26 GWOT ISHLAN 0 1 Wt ty sed 2 ES 0 5 T 82 ne AVMHSIH UNN A Jem aun JE t Sw FS TONINOISSINNOO3Q 1 1 9NINOISSINWOO Le Se re fees eI pi 92 7 Patent Application Publication Aug 21 2014 Sheet 2 of 5 US 2014 0236318 A1 CONTROLLER AIR SUPPLY MEASUREMENT FIG 2 N ci US 2014 0236318 A1 Aug 21 2014 Sheet 3 of 5 Patent Application Publication NOLLOV 31n93x1 31VNIAFT3 OL NOLLOV 3NIMH3I3Q ee ALFIOVA x9vadv3d JHL ONISN A8 YATIOULNOD OL VIVO NOILVOIGNI 31VO9INDnINWOO gel Alhlov4 wovgdv3s OL NOLLIINOO 1201 NI JO NOLLVOIQNI aay qr ind 9 vel NOILIGNOO 1530 NV NOILIQNOO
32. ss related constraints which may vary from one implementation to another More over it should be appreciated that such a development effort might be complex and time consuming but would neverthe less be a routine undertaking of design fabrication and manufacture for those of ordinary skill having the benefit of this disclosure 0014 When introducing elements of various embodi ments of the present invention the articles an the and said are intended to mean that there are or more of the elements The terms comprising including and hav ing are intended to be inclusive and mean that there may be additional elements other than the listed elements 0015 Certain industrial control systems include industrial controllers suitable for interfacing with a variety of field devices such as sensors pumps and valves For example an industrial controller may direct a pneumatic valve to set the valve s actuator at a certain position to affect the flow through the valve However desired functioning of the pneumatic valve may be affected by undesired conditions such as insuf ficient air pressure used to control the valve ora foreign object in the valve In order for the industrial controller to take appropriate ameliorative action undesired conditions may be detected and communicated to the industrial controller 0016 In field devices compliant with a Foundation Field bus protocol the field d
33. tatus is read by control function block 158 the control function block 158 may automatically use the control strategy 164 to determine an ameliorative action process block 182 For example the control function block 158 may use a second field device like an alternative valve as a backup This provides for redundancy in the opera tion for the first field device Other ameliorative actions include shutting down a pump disallowing the process to start issuing alerts communicating with an operator or with other systems In addition when the control function block 158 is a PID control function block 158 the PID control function block 158 may stop integrating the error and chang ing the SetPoint This may assist in a faster recovery because once recovered the Output Block 160 will resume using the most recent SetPoint Accordingly it should be appreciated that the integrating should cease as quickly as possible which may be accomplished through the techniques described herein Specifically the integrating may cease within one macrocycle 0041 Similar to reporting an undesired condition recov ery may be accomplished within one macrocycle In the recovery process the Output function block 160 may notify the control function block 158 using the same ReadBack facility Accordingly the control function block 158 may resume normal operation within one macrocycle or one con trol loop execution 0042 Inother embodiments such as i
34. vice 38 may be commissioned without using the placeholder In one embodiment field device 38 may be a flow control device such as a valve flow and or pressure regulator flow restrictor or any combination thereof For example the field device 38 may be a valve such as a pneumatic actuated valve a hydraulic actuated valve an electricity driven valve or any Aug 21 2014 combination thereof As described above undesired condi tions may hinder the operation ofthe field device 38 Accord ingly FIG 2 describes an exemplary pneumatic device as well as undesired conditions such as insufficient air pressure 0024 FIG 2 is a schematic diagram illustrating an embodiment of the industrial controller 30 controllably coupled to the pneumatic valve 38 of FIG 1 The pneumatic valve 38 may include a valve body a fluid path through the valve body an inlet and outlet and a valve member that move in the fluid path to open and close the flow path In addition the pneumatic valve 38 may includes a positioner 116 and an actuator 118 The positioner 116 may be configured to receive a desired valve position from the controller 30 and provide a signal such as air to the actuator 118 An exemplary posi tioner 116 may be General Electric s Masoneilan SVI digital valve positioner with built in magnetic position sensing and pressure sensors available from General Electric Co of Schenectady N Y The actuator 118 may then change the signal into m
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