LabView Users Group Meeting June 20 th, 2006 Process Control Using Compact Field Point/Labview Real-time Michael Tockstein Microelectronics Technology Department Electronics Photonics Laboratory June 20 th, 2006 LabView Users Group Meeting June 20 th, 2006

Outline Furnace Bank Control Application Overview Requirements of our System Compact Fieldpoint (cFP) Overview Connecting to cFP Labview Real-Time code structure Remote Panels Shared Variables Things to Remember about Real-Time Software LabView Users Group Meeting June 20 th, 2006

Our Control Project Gas Flow Wafer Processing LabView Users Group Meeting June 20 th, 2006

Furnace Bank

LabView Users Group Meeting June 20 th, 2006 Requirements Adaptable to Existing System Single cFP 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 LabView Users Group Meeting June 20 th, 2006

What is Real-Time? Independently Run Controllers Real-Time = Real Reliable

LabView Users Group Meeting June 20 th, 2006 Why cFP/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

LabView Users Group Meeting June 20 th, 2006 Compact FieldPoint Assembly Includes: –CPU and Process Control Module –Backplane –Digital and Analog I/O Modules –Connector Blocks LabView Users Group Meeting June 20 th, 2006

cFP Backplane 4 or 8 channel backplanes available I/O modules receive power directly from backplane NI data bus protocol LabView Users Group Meeting June 20 th, 2006

cFP Control Module Labview Real-Time code runs in on-board controller, not your PC Ethernet port Serial port VDC input. (20W power supply recommended) Provides power to backplane “cFP-2000” LabView Users Group Meeting June 20 th, 2006

Discrete Output Module 16 Channels, 2A sinking per channel Used for control of gas flow “cFP-DO-403” LabView Users Group Meeting June 20 th, 2006

Pulse Width Modulator (PWM) Module 8 channels of PWM Used for control of Watlow 100A Solid State Relay Firing Pulse period parameters set through “Measurement and Automation Explorer” (MAX) “cFP-PWM-520” LabView 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 “cFP-TC-120” LabView Users Group Meeting June 20 th, 2006

Discrete Input Module 32 digital input channels Compatible with 24VDC sourcing-output devices Used to read important indicators, (e.g. vacuum seal, etc…) “cFP-DI-304” LabView Users Group Meeting June 20 th, 2006

Connector Blocks Two types: –“cFP-CB-1” –“cFP-CB-3” Connected to corresponding module through backplane Used to physically wire devices to cFP unit LabView Users Group Meeting June 20 th, 2006

cFP Hardware Setup NI Measurement and Automation Explorer –Will “see” any NI hardware on the network –Assign IP address –Set parameters –Ready to Go!

LabView Users Group Meeting June 20 th, 2006 User Specified Inputs For cFP System

LabView Users Group Meeting June 20 th, 2006 Components of the Real-Time Software “Drivers” for each cFP 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 LabView Users Group Meeting June 20 th, 2006

cFP Module “Drivers” in LV 7.1 LabView Users Group Meeting June 20 th, 2006

“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.

LabView Users Group Meeting June 20 th, 2006 Drag and Drop “Drivers” For Each Device Channel Source: [1]

LabView Users Group Meeting June 20 th, 2006 What is PID? Proportional-Integral-Derivative PID Compensator SYSTEM +-+- Desired Setpoint

LabView Users Group Meeting June 20 th, 2006 PID Control Blocks Necessary for each zone of our temperature controller LabView Users Group Meeting June 20 th, 2006

High Level Program Flow Chart User Enters Table Values Start Program Read Inputs From cFP Compare Inputs To Table Activate Desired Outputs Set Center Zone Temperature Set Delay Counter Compare Delay Counter to Zero Increment Row Counter Reset Column Counter Increment Column Counter Increment Column Counter Increment Column Counter Outer Zones Track Center Zone Temperature True False True

LabView Users Group Meeting June 20 th, 2006 Program Step Code Reads Table Determines if input requirements are met Activates desired outputs Sets new temp Waits a desired time before next step

LabView Users Group Meeting June 20 th, 2006 Program Table LabView 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 = N2 NH3 H2SiCl2 GateValve A B C D Want = On OFF OFF On On Off On On Binary = b = 155d Tech enters 155 into table. Independent number conversion needed to save memory space onboard real-time controller. LabView Users Group Meeting June 20 th, 2006

Control Panel Available on host PC and remote window. LabView 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

LabView 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

LabView 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

LabView Users Group Meeting June 20 th, 2006 Summary Advantages of using cFP w/ LV Real-Time: –Very Flexible –Expandable –Relatively Easy to Understand –Simple Network Interface Disadvantages: –Limited Memory –Expensive LabView Users Group Meeting June 20 th, 2006

References [1]NI LabView Real-Time Hands-On Seminar Manual. February 2006 Edition. Part Number C-01 Additional Resources I.National Instruments: II.Compact Field Point: III.Labview Tour:

LabView Users Group Meeting June 20 th, 2006 Thank You! Questions, Comments, and Suggestions Welcome!