YOKOGAWA Admag TI AXG, Руководство пользователя

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<5. Functions>
86
IM 01E21A02-03EN
IMPORTANT
When using the DC power as the transmitter power, set the commercially available power
frequency of the place where the transmitter will be used.
Set “Power sync on/off” to Off and then set “Set power freq”.
The excitation frequency and power frequency can be checked with the following parameters.
Menu path
Display Device setup ► Detailed setup ► AUX calculation ► (see below)
F
OUNDATION
Fieldbus
Device Configuration ► STB ► Device Configuration ► Configuration ► AUX Calculation
Block
Name
Relative
Index
Parameter
Description
Display F
OUNDATION
Fieldbus
STB 95 Iex power frequency Iex Power Frequency
Displays the power frequency
(synchronous with the
excitation frequency).
STB 96 Meas power freq Mes Power Frequency
Displays the measured power
frequency.
5.5.5 Density Correction Calculation
When the temperature from other product (temperature transmitter, etc.) is obtained from MAO,
the density correction calculation can be performed based on temperature. The measurement
accuracy for the mass flow rate is improved by using this function.
The mass flow rate is calculated using the following formula.
V
m
=V
f
x ρ
V
m
: Mass flow rate [kg/s]
V
f
: Volumetric flow rate [m
3
/s]
ρ: Density [kg/m
3
]
When the density correction calculation is performed based on temperature, the density is
obtained using the following formula. The density compensating rates must be specified based
on applications that use this product.
ρ
r
=ρ
n
×{1+a
1
×(T
r
-T
n
)×10
-2
+a
2
×(T
r
-T
n
)
2
×10
-6
}
ρ
r
: Density corrected based on the measured temperature [kg/m
3
]
ρ
n
: Standard density [kg/m
3
]
T
r
: Measured temperature [°C]
T
n
: Standard state temperature [°C]
a
1
: Primary compensating rate
a
2
: Secondary compensating rate
This function can be used only for AXG, not for AXW. The standard temperature and the
compensating rates can be configured with the following parameters.
Menu path
Display Device setup ► Detailed setup ► Pro var ► Temperature ► (see below)
F
OUNDATION
Fieldbus
Device Configuration ► STB ► Device Configuration ► Configuration ► Process
Variables ► Temperature ► (see below)