The document addresses the accuracy of flow meters and provides an outline of flow measurement basics, types of wastewater treatment plant (WWTP) flow meters, and factors affecting accuracy. It includes case studies showcasing expected accuracies, considerations for different types of meters, and common causes of inaccuracies. Methods to verify flow meter accuracy are also discussed, along with layout and design considerations.

1. Is Your Flow Meter Accurate?

2. Is Your Flow Meter Accurate?
How Do You Know Your Flow Meter Is Accurate?

3. Is Your Flow Meter Accurate? How Do You Know Your Flow Meter Is Accurate? What’s Your Level of Confidence That Your Flow Meter is Accurate?

4. Outline
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5. Basics of Flow Measurement
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6. Basics of Flow Measurement
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7. Typical Types of WWTP Flow Meters
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8. Typical Types of WWTP Flow Meters
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9. Accuracy vs. Precision/Repeatability

10. Accuracy vs. Precision/Repeatability
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11. Accuracy vs. Precision/Repeatability
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12. Expected Accuracies: +/-
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13. Example Case Studies
WWTP 1
0.80 MGD Design
Jan. –Dec. 2012
WWTP 2
4.0 MGD design
Jan. –Dec. 2013
Influent
0.405 MGD
(1.16 MGD maxday)
3.045 MGD
(8.83MGD max day)
Effluent
0.211 MGD
(0.708 MGD max day)
3.483 MGD
(9.5 MGD max day)
92% difference
14% difference
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14. Considerations –Mag Meters
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15. Considerations –Mag Meters
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16. Considerations –Clamp-On Meters
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17. Considerations –Clamp-On Meters
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18. Considerations –Flumes
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19. Considerations –Weirs
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20. Considerations –Ultrasonic Level Transducers
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21. Layout & Design -Flumes
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22. Layout & Design -Weirs

23. Layout & Design

24. Layout & Design –Closed Pipe
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25. Layout & Design –Closed Pipe
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26. Common Causes of Problems (i.e., Inaccuracy)
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27. Common Causes of Problems (i.e., Inaccuracy)
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28. Common Causes of Problems (i.e., Inaccuracy)

29. Common Causes of Problems (i.e., Inaccuracy)
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30. Methods to Check

31. Methods to Check
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32. Methods to Check
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33. Methods to Check
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34. Summary
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35. Questions