KEP ES749 - 3.11 Liquid Sensible Heat; 4.2 Typical Wiring Connections

ES749 Flow Computer
21
3.11 Liquid Sensible Heat
Measurements:
Actual volume ow is measured by the ow element (DP transmitter, Flowmeter).
Temperature is measured by the temperature transmitter. A pressure transmitter can be
used to monitor pressure. Pressure measurement does not affect the calculation.
Calculations:
• The density, mass ow and sensible heat are calculated using the uid characteristics
stored in the ow computer. (see "FLUID DATA" submenu)
Output Results:
• Display Results
Sensible Heat, Mass or Volume Flow Rate, Resettable Total, Non-Resettable
Total, Temperature, Pressure, Density (optional: peak demand, demand last
hour, time/date stamp)
• Analog Output
Sensible Heat, Mass or Volume Flow Rate, Temperature, Pressure, Density,
Peak Demand, Demand Last Hour
• Pulse Output
Sensible Heat, Mass or Volume Total
• Relay Outputs
Sensible Heat, Mass or Volume Flow Rate, Total, Temperature, Pressure Alarms,
Peak Demand, Demand Last Hour
Applications:
Calculate the energy stored in a condensate with respect to water at 32°F (0°C).
LIQUID SENSIBLE
HEAT
Liquid Sensible Heat
Illustration
Volume Flow
As calculated in section 3.8
Heat Flow
Heat Flow = C • volume ow • (1-α • (T
1
-T
ref
))
2
• ref. density • (T
1
- 32)
α = Thermal expansion coefcient • 10
-6
C = Specic heat
Calculations
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
T
1