Liquid Controls WinHost Operation - Manual (Page 33)

33
Method 2 - Field Proving Technique
In situations where the meter’s accuracy curve is not
provided by the manufacturer, Multi-point Calibration
must be performed by proving the meter at various flow
rates.
1. Verify that “Linearization” is set to “SETUP”.
2. Start a proving run by pressing the START/RESUME
Key on the Laptop keypad. Monitor SCREEN 12 -
“PRODUCT CALIBRATION” during this proving run.
The meter should be running at the normal high flow
rate. The “Flow Rate” field displays the current flow
rate of the meter.
3. When the prover is full, press the PRINT/END Key
on the keypad.
4. Move the pointer to “Prover Quantity” and press
ENTER to open a Field Edit Window to enter the
exact quantity shown in the prover.
5. From SCREEN 13 - PRODUCT CALIBRATION,
move the pointer to “Point Number” and press the
ENTER Key to open a List Box Window and verify
that “Linearization Point” is set to “1”. Press EN-
TER.
6. Press START/RESUME to begin a new prover run
at the same flow rate as Step 2. Note the maximum
flow rate observed during the proving run. When
the prover is full, press PRINT/END.
7. Move the pointer to “Prover Quantity” and press
ENTER to open a Field Edit Window and enter the
exact quantity shown in the prover. When this is
entered, the “Percent Error” field will update to show
the calculated error for that flow rate.
8. Move the pointer to “Flow Rate” and press ENTER
to open a Field Edit Window and enter the maximum
flow rate observed during the run. Press ENTER.
9. Move the pointer to “Point Number” and press EN-
TER to open a List Box Window for “Linearization
Point” and select the next point number, “2”.
10. Begin a second prover run at a different flow rate.
Press START/RESUME and monitor the display for
maximum flow rate for the run. When the prover is
filled, press PRINT/END.
Multi-Point Calibration
11. Move the pointer to “Flow Rate” and press ENTER
to open a Field Edit Window and enter the maximum
flow rate observed during the run. Press ENTER.
12. Continue proving at various flow rate using additional
“Point Numbers” and repeat the procedure (return
to Step 7) for each additional number. A minimum of
three points is recommended (high, medium, and
low) to obtain a good fit to the meter’s curve.
All ten points can be used to obtain optimum results.
Any unused points should be left at “0.00” for “Flow
Rate” and “0.000” for “Percent Error”.
13. When all the required points have been calibrated,
move the pointer to “Linearization” and press EN-
TER to open a List Box Window and select “AP-
PLIED”. This puts the Linearization algorithm into
effect. If the error message “ADJACENT POINTS
OUT OF 0.25% RANGE” is displayed, APPLIED will
not take effect and more points will need to be added
to ensure that no two adjacent points, based on flow
rate, are more than 0.25% apart in their correspond-
ing “Percent Error” fields.