Emerson Oxymitter 5000 Instruction Manual page 138

Model 4081FG Oxygen Analyzer with F
Application Example: Pressure
Transmitter used to Measure
Level in an Open Tank
FIGURE B-4. Situation #1 Diagram.
TABLE B-4. Analog Input Function
Block Configuration for a Pressure
Transmitter used in Level Measurement
(situation #1).
FIGURE B-5. Function Block Diagram
for a Pressure Transmitter used in Level
Measurement.
B-10
fieldbus Communications
OUNDATION
Situation #1
The level of an open tank is to be measured using a pressure tap at the
bottom of the tank. The level measurement will be used to control the
level of liquid in the tank. The maximum level at the tank is 16 ft. The
liquid in the tank has a density that makes the level correspond to a
pressure of 7.0 psi at the pressure tap (see Figure B-4).
16 ft
Solution to Situation #1
Table B-4 lists the appropriate configuration settings, and Figure B-5
illustrates the correct function block configuration.
Parameter
L_TYPE
XD_SCALE
OUT_SCALE
Analog
Measurement
AI
Function
Block
BKCAL_IN
PID
Function
Block
CAS_IN
Full Tank
7.0 psi measured at
the transmitter
Configured Values
Indirect
0 to 7 psi
0 to 16 ft
OUT_D
OUT
OUT CAS_IN
BKCAL_OUT
AO
Function
Block