User Manual
E018-P
Page 26
FW_E018-P_M_v0301-01_EN
KF0
KF0
64
93
161
336
514
10,000
Frequency
Hz
K-Factor
KF0=51.64178
KF1=35.7 @ 64Hz.
KF2=47.5 @ 93Hz.
KF3=53.8 @ 161Hz.
KF4=49.2 @ 336Hz.
KF5=52.9 @ 514Hz.
KF1
KF2
KF3
KF4
KF5
MF1=0.691300
MF2=0.919798
MF3=1.041792
MF4=0.952717
MF5=1.024364
0
0
35.7
51.6
Fig. 16:
Example of K-Factors and linearization points
When a new frequency is measured, the corresponding Meter Factor is calculated by interpolating
between the linearization points. The new Meter Factor is then used to calculate the actual K-factors
for flowrate and total using this formula:
When the measured frequency is below the lowest or above the highest frequency given in the
linearization points, the Meter Factor belonging to that frequency is used.
Entering linearization points
A table of 15 linearization points can be entered into the unit. It is advised to enter the linearization
points in increasing order of frequency; however, this is not mandatory. The linearization points are
usually located at frequencies where the linear behavior of the flowmeter changes. Linearization
points that are not used can be disabled by entering a frequency of 0 Hz.
The following formula can be used to calculate the Meter Factors for the linearization points:
In this formula, the value of
KF0
represents the average K-factor of the flowmeter and
KFx @ flow x
represents the actual K-factor (derived from the actual flow) at the selected frequency (note that the
K-factors must be in the same engineering units (e.g. pulses / GAL) to perform the calculation).
K-factors entered at
1.3: TOTAL > K-FACTOR
and
2.4: FLOWRATE > K-FACTOR
can have different engineering
units, but make sure they represent the same ‘average value’ as
KF0
.
6
LINEARIZATION
6.1..
.F
FREQ. / M-FACTOR
1 ... 15
The M Factor is displayed on the top line of the display. A value between
0.000001 and 9.999999 can be entered. Most M-factors will be around
1.000000, for example 0.945354 or 1.132573.
The frequency is displayed on the bottom line of the display. The maximum
frequency is 9,999.9 Hz. When 0.0 Hz is selected, the M Factor is disabled
(
SETUP
6.H: LINEARIZATION > DECIMALS FREQUENCY [»27]
).