Emerson Fisher 249VS Instruction Manual
www.Fisher.com
1. Note that this document does not consider the effects of the thermal expansion of
the moment arm, or the thermal expansion of displacer volume.
Simulation of Process Conditions for Calibration
of Fisher
r Level Controllers and
Transmitters—Supplement to 249 Sensor
Instruction Manuals
Displacer / torque tube sensors are transducers that convert a buoyancy change into a shaft rotation. The change in
buoyancy is proportional to the volume of fluid displaced, and the density of the fluid. The change in rotation is
proportional to the change in buoyancy, the moment arm of the displacer about the torque tube, and the torque rate.
The torque rate itself is a function of the torque tube material, the temperature of the material, the wall thickness, and
the length. If the density of the process fluid, process temperature, and torque tube material of the sensor are known,
simulation of process conditions may be accomplished by one of the following means(1):
1. Weight or Force Method:
The interface application is the most general case. The level application can be considered an interface with the upper
fluid SG
= 0, and the density application can be considered as a variable SG application with the interface at the top of
the displacer. The buoyancy for a given interface level on the displacer is given by:
FB
SGU)Hdisp *
]
[
=
* VD *
(1)
ρw
(SGL - SGU )
Where:
FB
= buoyant force
ρw
= density of water at 4
_C, 1
atmosphere = 1.0000 Kg/liter
(0.03613 lb/in3)
VD
= displacer volume
Hdisp
= height of interface on displacer,
normalized to displacer length
SGU
= specific gravity of upper fluid
(0.0 for Level)
SGL
= specific gravity of lower fluid
Figure 1. Cutaway View of Fisher 249 Displacer
Sensor
LIQUID DISPLACER
TORQUE TUBE
W2141-1
SUSPENSION ROD
DRIVER ROD
Instruction Manual Supplement
D103066X012
249 Sensors
March 2014
Also See for Emerson Fisher 249VS
Related Manuals for Emerson Fisher 249VS
-
Emerson Field Instrumentation Fisher 249 249B 249BF 249C 249K & 249L Data Sheet
16 pages
-
Emerson Field Instrumentation Fisher 249 249B 249BF 249C 249K & 249L Data Sheet
16 pages
-
Emerson Field Instrumentation Fisher 249 249B 249BF 249C 249K & 249L Instruction Manual
12 pages
-
Emerson Field Instrumentation Fisher 249P 249BP & 246CP Data Sheet
16 pages
-
Emerson Field Instrumentation Fisher 249P 249BP & 246CP Data Sheet
20 pages
-
Emerson Field Instrumentation Fisher 249P 249BP & 246CP Instruction Manual
12 pages
-
Emerson Field Instrumentation Fisher 249W Data Sheet
20 pages
-
Emerson Field Instrumentation Fisher 249W Instruction Manual
20 pages
-
Emerson Field Instrumentation Fisher 2625 & 2625NS Data Sheet
8 pages
-
Emerson Field Instrumentation Fisher 2625 & 2625NS Instruction Manual
12 pages
-
Emerson Field Instrumentation Fisher 377 Instruction Manual
20 pages
-
Emerson Field Instrumentation Fisher 4194 Instruction Manual
100 pages
-
Emerson Field Instrumentation Fisher 4195K Instruction Manual
124 pages
-
Emerson Field Instrumentation Fisher 4200 Instruction Manual
48 pages
-
Emerson Field Instrumentation Fisher 4320 Instruction Manual
8 pages
-
Emerson Field Instrumentation Fisher 4660 Data Sheet
12 pages
-
Emerson Field Instrumentation Fisher 4660 Instruction Manual
4 pages
-
Emerson Field Instrumentation Fisher 4660 Instruction Manual
24 pages
-
Emerson Field Instrumentation Fisher 546 Instruction Manual
24 pages
-
Emerson Field Instrumentation Fisher 546 Instruction Manual
24 pages
-
Emerson Field Instrumentation Fisher 646 Data Sheet
8 pages
-
Emerson Field Instrumentation Fisher 846 Instruction Manual
52 pages
-
Emerson Field Instrumentation Fisher C1 Instruction Manual
52 pages
-
Emerson Field Instrumentation Fisher i2P-100 Instruction Manual
28 pages