Emerson Oxymitter 5000 Instruction Manual page 140

Model 4081FG Oxygen Analyzer with F
Application Example:
Differential Pressure Transmitter
to Measure Flow
TABLE B-6. Analog Input Function
Block Configuration for a Differential
Pressure Transmitter.
FIGURE B-7. Function Block Diagram
for a Differential Pressure Transmitter
Used in a Flow Measurement.
Analog
Measurement
AI
Function
Block
B-12
OUNDATION
Situation
The liquid flow in a line is to be measured using the differential
pressure across an orifice plate in the line, and the flow measurement
will be used in a flow control loop. Based on the orifice specification
sheet, the differential pressure transmitter was calibrated for 0 to 20
inH 0 for a flow of 0 to 800 gal/min, and the transducer was not
2
configured to take the square root of the differential pressure.
Solution
Table B-6 lists the appropriate configuration settings, and Figure B-7
illustrates the correct function block configuration.
Parameter
L_TYPE
XD_SCALE
OUT_SCALE
BKCAL_IN
OUT_D
OUT IN
fieldbus Communications
Configured Values
Indirect Square Root
0 to 20 in.
0 to 800 gal/min.
PID
Function
Block
BKCAL_OUT
AO
Function
Block