Oval EL4301, Instructions Manual

Page: 15 / 24

E-886-2-E
1
7. CALCULATION FORMULAS
Table 7.1
Calculate Item
(Models)
Calculation Formula
Density before
correction
(EL4301)
(EL4311)
T
x2
(1 －α t
x
) － T
a2
(1 －α t
a
)
D
x
＝ (D
w
－ D
a
) {
)
＋ D
a
［ g/ml ］
T
w2
(1 －α t
w
) － T
a2
(1 －α t
a
)
Where D
w
: Density of water ［ g/ml ］
t
w
: Temperature of water during calibration ［° C ］
α : Temp. correction factor of tube spring const. ［ %/ ° C ］
T
w
: Density period of water ［μ s ］
t
a
: Temperature of air during calibration ［° C ］
t
x
: Line temperature ［° C ］
T
a
: Density period with air ［μ s ］
T
x
: Density period ［μ s ］
D
a
: Density with air ［ g/ml ］
Corrected dens.
(EL4301)
(EL4311)
D
xc
＝ D
x
＋ β (t
x
－ t
o
) ［ g/ml ］
where β :Thermal expansion coeff. of fluid ［ g/ml/ ° C ］ t
o
: Ref. temp. for temp. correction ［° C ］
%MASS
(EL4301)
D
4
(D
xc
－ D
3
)
%MASS ＝ × 100 ［ % ］
D
xc
(D
4
－ D
3
)
where D
3
: Density of carrier fluid ［ g/ml ］ for calculation of %MASS (others)
D
4
: Density of target fluid ［ g/ml ］
Total mass flow
(EL4311)
E
Q
u
＝ a × I
p
÷ (1 ＋ ) ［ kg ］
100
where a: Meter factor ［ kg/P ］ I
p
: Number of input pulses E: Meter error correction ［ % ］
Total flow of sol-
ids content
(EL4311)
X
s
Q
a
＝ Q
u
× ［ kg ］ X
s
＝ (D
a
＋ D
b
・ D
x
＋ D
c
・ D
x2
) × (T
a
＋ T
b
・ t
x
＋ T
c
・ t
x2
) ［ % ］
100
where X
s
: Solids proportion D
a
to D
c
, T
a
to T
c
: Coefficients to determine X
s
Instant flowrate
of solids content
(EL4311)
X
s
E
Q
sr
＝ Q
r
× ［ kg/h ］ Q
r
＝ a × f ÷ (1 ÷ ) × 3600 ［ kg/h ］
100 100
where f: Input frequency ［ Hz ］ E: Meter factor correction ［ % ］
Density before
correction
(EL4321)
(EL4331)
2 ・ d
o
(T － T
o
') 2
d ＝ ・ [(T － T
o
') ＋ K ] ［ g/l ］ T
o
' ＝ T
o
＋ α (t － t
cal
) ［μ s ］
T
o
' 2T
o
'
where T: Period time during meas. ［μ s ］ d
o
: Constants Gas service: 70 ［ g/l ］ ± 10%
t: Line temperature ［° C ］ Liquid service: 210 ［ g/l ］ ± 10%
T
o
: Period time under vacuum Gas service: 350 ［μ s ］ ± 10%
Liquid service: 180 ［μ s ］ ± 10%
t
cal
Temperature during calib. ［° C ］ α : Temperature coeff. ［μ s/ ° C ］ K: Constant
Corrected
density
(EL4321)
t
x
＋ 273.15 P
o
＋ 0.101325 1
dN ＝ d ・ ・ ・ ［ g/l ］
t
o
＋ 273.15 P
x
＋ 0.101325 X
X ＝ (P
a
＋ P
b
・ P
x
＋ P
c
・ P
x2
) × (T
a
＋ T
b
・ t
x
＋ T
c
・ t
x2
)
where T
o
: Reference temperature ［° C ］ T
x
: Temp. during measurement ［° C ］
P
o
: Reference pressure ［ MPa (gauge) ］ P
x
: Press. during meas. ［ MPa (gauge) ］
X: Compressibility coeff. P
a
to P
c
, T
a
to T
c
: Factors to calculate compressibility coeff.
Corrected
density
(EL4331)
dN ＝ d ＋ β (t
x
－ t
o
) ［ g/l ］
where
β : Thermal expansion coeff. of fluid ［ g/l/ ° C ］
Analog output
(EL4321)
(EL4331)
dN － dB
I ＝ ( × 16) ＋ 4 ［ mA ］
Density Span
where dB: Base density ［ g/L ］
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