Liquid Controls SP4000 - Manual (Page 19)

SP4000 Flow Computer
16
3.4 Corrected Liquid Volume
Measurements:
A flowmeter measures the actual volume flow 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 flow and temperature inputs as well as the
thermal expansion coefficient stored in the flow computer (see "FLUID DATA"
submenu). Use the "OTHER INPUT" submenu to define 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 flow 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. flow • (1 -
α
• (Tf-Tref)) 2
α
= Thermal expansion coefficient • 10 -6
Calculations
Corrected
Liquid Volume
Illustration
Flowmeter Temperature
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