Yearly Metering & Flow Computer Totalizer Check FQI (FLOW TOTALIZER FLOW COMPUTER LACT UNIT)

Procedure for Totalizer Checks as Part of the Calculation Checks:

1. Ensure that flow has been completely stopped through the stream to be checked.

2. Make sure the Meter active flag is false by entering a positive value for low flow cut off. (See Omni User manual)

3. Using the Omni Flow computer Keypad, press (Alpha Shift), (Prog), (Meter), (n), (Enter).

4. Press the down arrow key until you reach Toggle Maintenance Mode.

5. Press (Alpha), (Shift), (Y), (Enter), this will toggle the maintenance mode on or off depending on current status.

6. You will be asked for the level 1 password, after entering the password press, (Enter).

7. To end or deactivate the mode at any time follow steps 1 to 5, the display will show if Maintenance mode is active or not with Maintenance Mode Y or N.

8. Now that you are in Maintenance Mode all the primary Totalizers will not accumulate during testing. The Maintenance Totals can also be reset at any time whilst in Maintenance Active mode.

9. Set the Temperature, Pressure and / or Density (if applicable) values close to line conditions by setting the appropriate input Override code to "1". (This causes the default fixed value to be used at all times) These must be returned to "3" at the end of testing. This option which is the normal running condition, means that in the event of an input failure, the average of the last hours input value will be used as a fixed override value.

Note: Currently, on the two allocation metering systems, only the Gross flow figures are being used, and the Net volume and Mass figures are disregarded. As long as this is the case this step can be disregarded.

10. Due to the resolution of the Omni Display set the K-Factor to a figure of value that will highlight a single pulse error should it occur. Be sure to record the current in use K-Factor Value. Note: a good figure to use for K-Factor would be 10 as this would show a single pulse error as 0.1 m3 vol.

11. Replace the Turbine Meter pulse inputs with the turbine meter simulator and connect the timer counter across the simulator output as an extra check. Note care must be taken when connecting or disconnecting inputs, lift fuses to pre-amps prior to performing this task.

12. Set the Simulator to a frequency similar to that of normal operation and note the Flow rate, it should be as expected for the frequency applied.

13. Switch off the Simulator and reset the Maintenance totals and the Timer / Counter.

14. The test can be performed in two ways either injecting a known amount of pulses from the Simulator or fixing a set frequency and recording the total pulses from the timer counter.

15. A sufficient amount should be collected, i.e. at a nominal flow rate of 450m3/hr and a K- Factor of 6500.00 pulse/m3 would require a frequency of 812.5Hz. There for injecting 48750 pulses would take 60 sec or 1 minute.

16. Depending on whether the computer is set up to calculate Net and Mass or only Gross totals these must be recorded and verified on the Calibration spreadsheet to within the specified tolerances.

17. Repeat the test 3 times and check that all the results are acceptable.

18. If all results are ok disconnect the test equipment and replace the inputs with the Turbine Meter for the stream. Note care must be taken when connecting or disconnecting inputs, lift fuses to pre-amps prior to performing this task.

19. Remove all fixed input values for Temperature, Pressure and / or Density (If applicable).

20. Enter the current in use K-Factor back into the computer.

21. Return the computer to normal operation as stated in steps 1 to 5 and resume flowing through the stream.

22. Sign-off Work Permit and return to operations.

23. Report all findings to supervision and document in CMMS.