KEP ES749 - 3.8 Corrected Liquid Volume

ES749 Flow Computer
18
3.8 Corrected Liquid Volume
Measurements:
A owmeter measures the actual volume ow in a liquid line. A temperature sensor is
installed to correct for liquid thermal expansion. A pressure sensor can be installed to
monitor pressure. Pressure measurement does not affect the calculation.
Calculations:
• Corrected Volume is calculated using the ow and temperature inputs as well as
the thermal expansion coefcient stored in the ow computer (see "FLUID DATA"
submenu). Use the "OTHER INPUT" submenu to dene reference temperature and
density values for standard conditions.
Output Results:
• Display Results
Corrected Volume and Actual Volume Flow Rate, Resettable Total, Non-
Resettable Total, Temperature, Pressure, Density (optional: peak demand,
demand last hour, time/date stamp)
• Analog Output
Corrected Volume and Actual Volume Flow Rate, Temperature, Pressure,
Density, Peak Demand, Demand Last Hour
• Pulse Output
Corrected Volume and Actual Volume Total
• Relay Outputs
Corrected Volume and Actual Volume Flow Rate , Total, Pressure, Temperature
Alarms, Peak Demand, Demand Last Hour
Applications:
Monitoring corrected volume ow and total of any liquid. Flow alarms are provided via
relays and datalogging is available via analog (4-20mA) and serial outputs.
Corrected
Liquid Volume
Volume Flow
Pulse Input; Average K-Factor
input frequency • time scale factor
Volume Flow =
K-Factor
Analog Input; Linear
Volume Flow = % input • Full Scale Flow
Corrected Volume Flow
Corrected Volume Flow = vol. ow • (1 - α • (Tf-Tref))
2
α = Thermal expansion coefcient • 10
-6
Calculations
Corrected
Liquid Volume
Illustration
FlowmeterTemperature
Transmitter
PRINT
5
0
–
TIME
CLEAR
•
MENU
ENTER
HELP
TEMP
4
PRE 1
3
RATE
2
TOTAL
1
GRAND
6
SCROLL
7
PRE 2
8
DENS
9
Optional
Pressure
Transmitter