Instruction Manual

Instruction Manual
D102748X012
Introduction and Specifications
October 2014
10
Table 1‐3. 249 Sensor Specifications
Input Signal
Liquid Level or Liquid‐to‐Liquid Interface Level:From 0
to 100 percent of displacer length
Liquid Density: From 0 to 100 percent of
displacement force change obtained with given
displacer volume—standard volumes are
J980 cm
3
(60 inches
3
) for 249C and 249CP sensors or J1640
cm
3
(100 inches
3
) for most other sensors; other
volumes available depending upon sensor
construction
Sensor Displacer Lengths
See tables 1‐6 and 1‐7 footnotes
Sensor Working Pressures
Consistent with applicable ANSI
pressure/temperature ratings for the specific sensor
constructions shown in tables 1‐6 and 1‐7
Caged Sensor Connection Styles
Cages can be furnished in a variety of end connection
styles to facilitate mounting on vessels; the
equalizing connection styles are numbered and are
shown in figure 1‐3.
Mounting Positions
Most level sensors with cage displacers have a
rotatable head. The head may be rotated through
360 degrees to any of eight different positions, as
shown in figure 2‐5.
Construction Materials
See tables 1‐5, 1‐6, and 1‐7
Operative Ambient Temperature
See table 1‐4
For ambient temperature ranges, guidelines, and use
of optional heat insulator, see figure 2‐7.
Options
J Heat insulator, see description under Ordering
Information
J Gauge glass for pressures to 29 bar at
232_C (420 psig at 450_F), and
J Reflex gauges for
high temperature and pressure applications
Table 1‐4. Allowable Process Temperatures for
Common 249 Sensor Pressure Boundary Materials
MATERIAL
PROCESS TEMPERATURE
Min. Max.
Cast Iron -29_C (-20_F) 232_C (450_F)
Steel -29_C (-20_F) 427_C (800_F)
Stainless Steel -198_C (-325_F) 427_C (800_F)
N04400 -198_C (-325_F) 427_C (800_F)
Graphite
Laminate/SST
Gaskets
-198_C (-325_F) 427_C (800_F)
N04400/PTFE
Gaskets
-73_C (-100_F) 204_C (400_F)
Table 1‐5. Displacer and Torque Tube Materials
Part Standard Material Other Materials
Displacer 304 Stainless Steel
316 Stainless Steel,
N10276, N04400,
Plastic, and Special
Alloys
Displacer Stem
Driver Bearing,
Displacer Rod
and Driver
316 Stainless Steel
N10276, N04400,
other Austenitic
Stainless Steels, and
Special Alloys
Torque Tube N05500
(1)
316 Stainless Steel,
N06600, N10276
1. N05500 is not recommended for spring applications above 232_C
(450_F). Contact your Emerson Process Management sales office or
application engineer if temperatures exceeding this limit are required.