PI System Management Best Practices

1. PI System Management Best Practices Bryan S. Owen P.E. OSIsoft Field Service PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

2. Focus on Benefits Change Management Interacts with System Management! PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

3. Change Management and Continuous Improvement Typical PI Improvement Projects • Server Upgrades • Custom Applications • Raw Data Collection • Performance Calculations • Layered Data Structures • Desktop Deployments • Skill Development PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

4. PI Server Upgrade Stage Upgrade on Spare Platform • Preferred O/S – Windows 2K • Windows Domain Membership • Test with PItoPI or Parallel Interfaces Review PI Timeout Table • Maxupdatequeue, Totalupdatequeue, Readtimeout • http://support.osisoft.com/FieldService/service_downloads.htm Interface Status Watchdog (Optional) • “flatline” detection • optional status change for input points PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

5. Custom Application Guidelines Preferred Core PI Technology • SQL (OLEDB Provider) • OPC Server • SDK/API Deployment Hints • Dedicated PI User Name • Identify all Inputs and Outputs to PI • Assign DataOwner on Output Points PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

6. RtPM Pyramid Act Without Action, there is no Benefit People Need Pictures, Graphs, Trends Visualize Get the Information to People Who Need It Distribute Aggregation, Reconciliation, Calculation, Cases Analyze Execs Look for Equipment, Plants, Products, not Tags Assign Context Gather Data Collection from Inside and Outside the Corporation PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

7. Integrated Data Source Archive is provided by source system No data replication PI queries redirected to source host Constraints: scalability, connection latency Hot: OLEDB Connector Decoupled Data Source No archive retention burden on source host Scheduled replication PI queries resolved locally Constraints: scan rate and out of order data Hot: OPC Interface Connectors or Interfaces? PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

8. Data Source Reconciliation Periodic Discovery • Automatic Point Synchronization (yes, OPC connector!) • Dedicated workstation is suggested Point Deletion • Server concordance check (SMT advanced search…getpointssql) • Alternative: set ptaccess=“o: g: w:” PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

9. Point Type Selection …Float16 vs Float32 FLOAT32 is easy on the administrator but… • No under/over range sanity check (unless a supported by the interface). • Dirty zero affects aggregates differently (not reflected in percent good, use Totalizer with zerobias). • Performance penalty (~2x archive i/o). FLOAT16 rules of thumb… • Well defined zero and span required. • Large scale systems >50,000 pts. • Sub second data collection. • High data density applications (PI profile points). PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

10. Interface Accuracy Scan Class Schedules • Avoid schedule collisions Dedicated Instances • Load balancing and isolation • Event triggers and outputs • Special handling (stopstat, watchdog list) Report all changes to PI • Minimize Excdev (zero is ok!) • Buffer recovery is constraint PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

11. Compression Guideline Ideal: set based on process specification • usually <1% compression deviation Easy: use rated instrument precision • Excess archiving is a potential process issue or sampling limitation. • If possible, resolve “noise” at the source (filter may be an appropriate remedy). PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

12. RtPM Pyramid Act Without Action, there is no Benefit People Need Pictures, Graphs, Trends Visualize Get the Information to People Who Need It Distribute Aggregation, Reconciliation, Calculation, Cases Analyze Execs Look for Equipment, Plants, Products, not Tags Assign Context Gather Data Collection from Inside and Outside the Corporation PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

13. Layered Data Structures in PI Base • Digital Sets • Headings • Aliases • Properties • Modules Archive • Batch, UnitBatch/SubBatch, Transfers PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

14. Digital Sets System set is global • Applies to all points • Important factory defaults include • “Shutdown”, “Intf Shut”, “I/O Timeout” Digital points preferred over string tags • Enables multistate symbols and trends • Create dedicated state sets • Include placeholders for volatile sets PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

15. PI Headings…mutant Digital Sets! • Name, Level and Description • Level starts at 1 • Discontinuous sequences ok • Optional Module or SubBatch property PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

16. PI Alias Collections …Cached point lists • Organize points by module • Leverage utility with alias names • Multiple aliases for the same tag ok • Join tags from any number of servers Alias “aware” applications: • ACE, Batchview, MDB Editor • OLEdb Provider, OPC Server, SDK/API PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

17. PI Property Collections …Named Value Tables Collections in free format hierarchal structures. Associate nominally “static” properties with a Module. Stored in Archive when assigned to a Batch or Transfer Record. PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

18. PI Module Collections …File System for PI Free format hierarchy, a PI module may “link” to multiple collections. Access rights depend on DBsecurity and the root module owner. Versioning and query control based on “effective” date. “isPIunit” creates archive point for unitbatch recording. PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

19. Layered Data Structures in PI …Management Tips Restrict write access (DBsecurity default) • Digital Sets – PIDS • ModuleDB – PIModules, PIHeadingSets Standardize Digital Sets across an Enterprise • Especially useful with PItoPI implementation Configure ModuleDB with SDK/VB scripts: • Transmission Line Demo PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

20. RtPM Pyramid Act Without Action, there is no Benefit People Need Pictures, Graphs, Trends Visualize Get the Information to People Who Need It Distribute Aggregation, Reconciliation, Calculation, Cases Analyze Execs Look for Equipment, Plants, Products, not Tags Assign Context Gather Data Collection from Inside and Outside the Corporation PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

21. Server CalculationsPerformance Equation Study Over 15 servers & 5500 expressions • …expression length Median 50 characters, 95% < 162, Max=2851! • …archive function calls (~10% of total ) Median time span <9 hrs, Max since 1970! • …nesting levels (excluding circular logic) One Level 25%, Two Levels 9%, More 2.5% • …variables per expression (max=156!) PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

22. Performance Equation Study …Conclusions Primary Usage Analysis • simple transformations…y=mx+b, steam tables • data smoothing…tagavg, medianfilt • state detection / signal selector…if then else Conclusions • 80% of PE expressions are appropriate • 20% in need of redesign • Implement in ALARM or TOTAL processor • Logic or schedule more appropriate for ACE PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

23. Performance Equation Tips Develop Expressions on PI Desktop • Datalink “Expression Calculation” • Processbook “PI Dataset” Don’t implement on production servers until proven! Scheduling Options • Run simple transforms at raw scan rate • Uniint event triggers Event=‘motorstatus’ increment, (run on 0 -> 1 transition) • Enable Recalc for expressions with LAB inputs PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service

24. RtPM Pyramid Act Without Action, there is no Benefit People Need Pictures, Graphs, Trends Visualize Get the Information to People Who Need It Distribute Aggregation, Reconciliation, Calculation, Cases Analyze Execs Look for Equipment, Plants, Products, not Tags Assign Context Gather Data Collection from Inside and Outside the Corporation PI System Management – Best Practices Bryan S. Owen, OSIsoft Field Service