Calibration setup, Approximate k-factors, Multi-point calibration proving – Liquid Controls LCR 600 Setup & Op User Manual

Page 30

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30

approximate k-Factors

valueS are for provIng uSe only. not to be uSed aS actual K-factorS.

lc meter Size

Max Flow rate/Gallon

revs / gallon

pulses / gallon

pulses / litre

P

60

12.237

4894.8

1293.11

M/MA 5

60

4.079

1631.6

431.04

M/MA 7/10

150

5.555

2222.0

587.01

M/MA 15/25

300

2.058

823.2

217.47

M 30/40

450

0.742

296.8

78.41

M 60/80

800

0.398

159.2

42.06

MS-75

700

0.255

102.0

26.95

MS-120

1200

0.158

63.2

16.70

calIbratIon Setup

to prove a meter system to a product with multi-

point calibration:

1. With the selector switch in the calibration position,

navigate to the Calibration Setup 1 screen.

2. Use the instructions on the page 29 to run a single point

calibration.

3. Navigate to Calibration Setup 3. Move the pointer

 to

Linearization Mode:

and select Setup.

4. Move the pointer

 to the BeGIN CALIBRATION

deLIVeRY

field.

5. Press the

EntEr button to begin the calibration delivery

into a volumetric prover. A delivery screen will appear that

shows the gross volume and flow rate.

6. To end the delivery, move the pointer

 to the eNd

CALIBRATION deLIVeRY

field at the bottom of the

calibration delivery screen.

7. Move the pointer

 to the Prover Quantity: and

enter the quantity indicated by the volumetric prover.

8. The LCR 600 will automatically display a Point #: list

box with the numbers 1-10. Select a number.

9. The LCR 600 will then display a Linearization Flow

Rate

field edit box. Enter the flow rate of the proving run.

The percent error is calculated automatically.

multi-point calibration proving

Multi-point calibration improves the overall meter accuracy by flattening out the accuracy curve across flow rates.

Although accuracy tends to lessen at lower flow rates, the repeatability of the meter remains consistent. The meter

might not be perfectly accurate at low flow rates, but it is inaccurate the same amount each time. Multi-point calibration
takes advantage of the steadfast repeatability of a Liquid Controls meter by identifying the amount of inaccuracy and
correcting it with a linearizing algorithm during deliveries. In order to apply the linearizing algorithm, the degree of error

for points along the accuracy curve must be identified by making a number of deliveries at different flow rates into a

volumetric prover. Multi-point calibration is very beneficial for meter systems that experience a wide range of flow rates

(for example, trucks that fill tanks of varying sizes) and for meter systems that have recently undergone maintenance
or other alterations that could change the accuracy curve itself.

Run the first multi-point calibration delivery at the same

flow rate used in step 2.

Keep flow Rates Even

For the first two proving runs, one should be near the maximum

flow rate and one near the minimum flow rate of the meter.

When choosing flow rates after the initial two proving runs, split

the difference until all points are within 0.25% of each other.

Multi-point Calibration tip

Proving runs are in gross volume only.

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