Table of Contents
Advertisement
10.4 Electric Conductivity Correction
10.4.1
Standard conductivity correction factors
The indication of the density meter varies with the conductivity of the measured object fluid;
however, the variance is as small as approx. 0.15%TS to 1mS/cm change in conductivity and
usually practically negligible, thus making it unnecessary to input the conductivity meter signal to
perform electric conductivity correction. In the event that the conductivity change is large and thus
its impact is not ignoble, make sure to use the electric conductivity correction function. The formula
for this correction including the other corrections described in Chapter 9 is as follows.
△θ={θ2 -α（Τ-Τ０）-δ（Ｇ-Ｇ０）-ß (A-A
△θ
θ
2
θ
1
α
Τ
Τ
０
δ
Ｇ
Ｇ
０
γ
E
E
０
ß
Ａ
Ａ
０
At the time of factory shipment, the [electric conductivity correction factor γ] is set to zero for all
the products. If the conductivity change of the measured object fluid is large, input the electric
conductivity signal in accordance with "Fig.3.5 External Connection Diagram" and then reset the
[electric conductivity correction factor γ].
Table 10.4.1 shows the "standard values" of electric conductivity correction factors as well as the
"density line slope (a)" required in the event of obtaining electric conductivity correction factors
through calculation from measured values. The "standard values" shall be applicable when the
range of the electric conductivity meter used for conductivity correction is
0 to 10 mS/cm.
: Phase difference (degrees)
: Actual phase angle of measured object fluid (degrees)
: Phase during zero water measurement (degrees)
(Measured during zero calibration, and set in advance as a constant)
: Fluid temperature correction factor (degrees/℃)
: Fluid temperature of measured object fluid (℃)
: Water temperature during zero calibration
(Measured during zero calibration, and set in advance as a constant)
: RF correction factor
: RF data during measurement
: Zero point RF data
(Measured during zero calibration, and set in advance as a constant)
: Electric conductivity correction factor (degrees/(mS/cm))
:
Electric conductivity of measured object fluid (mS/cm)
: Zero water conductivity (mS/cm)
: Ambient temperature correction factor (degrees/℃)
: Ambient temperature (℃)
: Ambient temperature during zero adjustment
(Measured during zero point calibration, and set in advance as a constant)
) -γ(E-E０)} -θ1
0
87
6 F 8 A 0 5 2 1
Advertisement
Table of Contents
