Process Control Using Compact Field PointLabview Realtime Michael
Process Control Using Compact Field Point/Labview Real-time Michael Tockstein Microelectronics Technology Department Electronics Photonics Laboratory June 20 th, 2006 Lab. View Users Group Meeting June 20 th, 2006
Outline • • Furnace Bank Control Application Overview Requirements of our System Compact Fieldpoint (c. FP) Overview Connecting to c. FP Labview Real-Time code structure Remote Panels Shared Variables Things to Remember about Real-Time Software Lab. View Users Group Meeting June 20 th, 2006
Our Control Project • Wafer Processing 1 2 3 Gas Flow Lab. View Users Group Meeting June 20 th, 2006
Furnace Bank Lab. View Users Group Meeting June 20 th, 2006
Requirements • Adaptable to Existing System • Single c. FP Control Unit Covers: – – • • Process Sequence Controller Gas Flow Controllers Boat Loaders Four Three-Zone Furnace Tubes Programmable for new Process Graphical User Interface Remote Access from Office Technician Friendly Lab. View Users Group Meeting June 20 th, 2006
What is Real-Time? • Independently Run Controllers • Real-Time = Real Reliable Lab. View Users Group Meeting June 20 th, 2006
Why c. FP/LV Real-Time For Our System? • Eliminates need for separate controllers for each aspect of the process (i. e. gas flow, temp control, etc…) • Very customizable through both hardware and software • Best interface for our “individual” channels • Very reliable since VI runs independently from PC • Network Ready Lab. View Users Group Meeting June 20 th, 2006
Compact Field. Point Assembly • Includes: – – CPU and Process Control Module Backplane Digital and Analog I/O Modules Connector Blocks Lab. View Users Group Meeting June 20 th, 2006
c. FP Backplane • 4 or 8 channel backplanes available • I/O modules receive power directly from backplane • NI data bus protocol Lab. View Users Group Meeting June 20 th, 2006
c. FP Control Module • Labview Real-Time code runs in on-board controller, not your PC • Ethernet port • Serial port • 11 -30 VDC input. (20 W power supply recommended) • Provides power to backplane • “c. FP-2000” Lab. View Users Group Meeting June 20 th, 2006
Discrete Output Module • 16 Channels, 2 A sinking per channel • Used for control of gas flow • “c. FP-DO-403” Lab. View Users Group Meeting June 20 th, 2006
Pulse Width Modulator (PWM) Module • 8 channels of PWM • Used for control of Watlow 100 A Solid State Relay Firing • Pulse period parameters set through “Measurement and Automation Explorer” (MAX) • “c. FP-PWM-520” Lab. View Users Group Meeting June 20 th, 2006
Thermocouple Input Module • 8 channels of any type T/C • Used for temperature monitoring of the three zone heaters • Selection of T/C and Cal through MAX • Uses isothermal connector blocks • “c. FP-TC-120” Lab. View Users Group Meeting June 20 th, 2006
Discrete Input Module • 32 digital input channels • Compatible with 24 VDC sourcing-output devices • Used to read important indicators, (e. g. vacuum seal, etc…) • “c. FP-DI-304” Lab. View Users Group Meeting June 20 th, 2006
Connector Blocks • Connected to corresponding module through backplane • Used to physically wire devices to c. FP unit • Two types: – “c. FP-CB-1” – “c. FP-CB-3” Lab. View Users Group Meeting June 20 th, 2006
c. FP Hardware Setup • NI Measurement and Automation Explorer – Will “see” any NI hardware on the network – Assign IP address – Set parameters – Ready to Go! Lab. View Users Group Meeting June 20 th, 2006
User Specified Inputs For c. FP System Lab. View Users Group Meeting June 20 th, 2006
Components of the Real-Time Software • “Drivers” for each c. FP module • PID control blocks – Needed to control temperature • Program “step” code – Needed to take program through the logical sequence of events required for a specific process • Safety shutdown code – Temperature Overshoot – Zone Differential Exceeded – Manual Shutdown Lab. View Users Group Meeting June 20 th, 2006
c. FP Module “Drivers” in LV 7. 1 th, 2006 Lab. View 20 th 20 , 2006 Lab. View. Users. Group. Meeting. June
“Drivers” in Labview 8 • “Drivers” are much easier to implement in Labview 8. • Labview 8 has “drag and drop” features which allow you to drag a specific channel of a device (along with it’s “drivers”) over to your VI from the project window. Lab. View Users Group Meeting June 20 th, 2006
Drag and Drop “Drivers” For Each Device Channel Source: [1] Lab. View Users Group Meeting June 20 th, 2006
What is PID? • Proportional-Integral-Derivative Desired Setpoint + - PID Compensator Lab. View Users Group Meeting June 20 th, 2006 SYSTEM
PID Control Blocks • Necessary for each zone of our temperature controller Lab. View Users Group Meeting June 20 th, 2006
High Level Program Flow Chart User Enters Table Values False Compare Delay Counter to Zero Set Delay Counter True Start Program Increment Row Counter Increment Column Counter Read Inputs From c. FP Reset Column Counter Set Center Zone Temperature Compare Inputs False To Table Increment Column Counter True Increment Column Counter Lab. View Users Group Meeting June 20 th, 2006 Activate Desired Outputs Outer Zones Track Center Zone Temperature
Program Step Code • Reads Table • Determines if input requirements are met • Activates desired outputs • Sets new temp • Waits a desired time before next step Lab. View Users Group Meeting June 20 th, 2006
Program Table Lab. View Users Group Meeting June 20 th, 2006
Program Table Values • Decimal numbers correspond to a binary value which represents I/O ports. • Example for a particular output step: Actual = N 2 NH 3 H 2 Si. Cl 2 Gate. Valve A B C D Want = On OFF On On Off On On Binary = 1 0 0 1 1 10011011 b = 155 d Tech enters 155 into table. • Independent number conversion needed to save memory space onboard real-time controller. Lab. View Users Group Meeting June 20 th, 2006
Control Panel • Available on host PC and remote window. Lab. View Users Group Meeting June 20 th, 2006
Remote Panel • Built in Web server. • Monitor/control your application from a Web browser • Advantage to user running a long duration process Lab. View Users Group Meeting June 20 th, 2006
Shared Variables • Allows easy communication of data between Real. Time target VI and Host VI • Save program memory onboard Real-Time target by conducting most processing tasks on board PC using Host VI • Available only in Labview 8 Lab. View Users Group Meeting June 20 th, 2006
Things To Remember About The Real-Time Software • When you execute your program, it is downloaded and run on the Real-Time controller, not your PC! – This effects the size of your program and ultimately limits the number of “bells and whistles” you can have Lab. View Users Group Meeting June 20 th, 2006
Summary • Advantages of using c. FP w/ LV Real-Time: – Very Flexible – Expandable – Relatively Easy to Understand – Simple Network Interface • Disadvantages: – Limited Memory – Expensive Lab. View Users Group Meeting June 20 th, 2006
References [1] NI Lab. View Real-Time Hands-On Seminar Manual. February 2006 Edition. Part Number 351171 C-01 Additional Resources I. III. National Instruments: www. ni. com Compact Field Point: http: //www. ni. com/compactfieldpoint/ Labview Tour: http: //www. ni. com/swf/labview/us/tour Lab. View Users Group Meeting June 20 th, 2006
Thank You! Questions, Comments, and Suggestions Welcome! Lab. View Users Group Meeting June 20 th, 2006
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