Barksdale LSSM Level Site Supplemental Guide

LevelSite® Supplemental Guide
Level
Features
Model LSSM
in Typical System
Figure 1
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LevelSite® Supplemental Guide
General Specifications
Operating Principle
LevelSite® is a magnetic rotary indicator. It is a reliable level
measurement system for applications with operating pressures
to 4500 psig (310 bar), operating temperatures to 600°F
(316°C), and with liquid to a minimum specific gravity of 0.5049.
Figure 4
Interaction between Float and Flags
field from the permanent ring magnet acts on the magnets
embedded in each flag (See Figure
4). The rotating flags below the level
of the liquid in the float housing show
their red side and those above show
their white side.
The special permanent ring magnet
design provides a 360 degree
magnetic flux field. This allows the
rotating flag assembly, limit switches
and continuous level sensors to be
located anywhere around the float
housing. Troublesome guide wires
and rods, and magnetic tape on the
indicating flag housing are eliminated.
Figure 2
Typical System
LevelSite®’s visual indicators and electrical switches are isolated
from the liquid; the tank remains sealed from the surrounding
environment (See Figure 2). Accidental spills from sight-glass
breakage are eliminated.
LevelSite® consists of 3 major components: the float housing,
a magnetic float, and the rotating flag
assembly. The float housing is an engineered
pressure vessel which is externally mounted
to the tank. The float housing is designed
to handle the same temperatures and
pressures found in the tank. It is fabricated
from a variety of materials, depending on
the application. The alloy models are usually
stainless steel. Engineered plastic models use
polyvinylchloride (PVC), polypropylene (PP) or
polyvinyliden fluoride (PVDF). Other materials
are available on request.
Figure 3
The float (See Figure 3), is equipped with
Standard Alloy Float
a permanent ring magnet assembly. This
assembly rides at the surface of the liquid
contained within the float housing, rising and falling as the liquid
in the tank rises and falls.
As the float moves up and down, a magnetic flux field maintains
continuous contact with the rotating flags mounted on the
outside of the float housing. Flag rotation occurs as the flux
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Visual Indication
LevelSite®’s rotating flag assembly
provides maximum visibility and
has a resolution of 1/2” (12.7 mm).
Figure 5
Rotating flags have a square profile
with embedded permanent magnets. The flux field generated
by the ring magnet in the float interacts with the flag magnets
causing them to rotate as the float moves up and down inside
the housing. After the flags rotate to the new position, the
embedded magnets lock the flags in place, making the flags
less sensitive to vibration (See Figures 4 and 5).
LevelSite®’s rotating flags are mounted in a housing
fabricated of extruded aluminum
or polycarbonate. The assembly is
attached to the outside of the float
housing with stainless steel clamps.
The ends are sealed against dust
and moisture. Since the flags are
never in contact with the liquid, they
never need to be cleaned and they
can’t discolor. If the rotating flag
assembly is accidentally crushed,
there is no danger of a liquid spill.
The rotating flag assembly
is available in aluminum or
polycarbonate and measures 1.18”
Figure 6
(30 mm) and 1.02” (26 mm) wide,
respectively (See Figure 6).
Level
LevelSite® Supplemental Guide
General Specifications
Aluminum flags are offered in an anodized finish of red and
silver or painted in red and white. Anodized flags are suitable for
service up to 400°F (200°C); painted versions can be subjected
to 600°F (316°C). A glass pane protects the flags. The housing is
extruded, black anodized aluminum.
Polycarbonate flag housings are clear and impact-resistant.
They offer 180° visibility of the flags; level can be seen from
front and sides (See Figure 5). Housing and flags can withstand
temperatures to 250°F (121°C). Standard flag colors are red and
white.
System Specifications
LevelSite®s are designed according to the unique requirements
of each application. Based on information provided by the
user regarding operating temperature, pressure, and “normal”
specific gravity of the liquid, a float is selected appropriate to
the application. Maximum and minimum
conditions are evaluated to ensure that
the LevelSite® will function not only
at the normal condition, but at each
extreme. Maximum temperature and
pressure are parameters used to design
the pressure vessel (float housing).
Barksdale applies their own standards in
the design of LevelSite®s. Figures 8 and
9 can be used as a guide in selecting
the ANSI class flanges and materials
appropriate for your temperature and
pressure conditions.
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Material
Pressure/temperature performance parameters for LevelSite
housing constructed of 316 stainless steel are specified in the
chart. Please consult the factory with pressures/temperatures
requiring other alloys.
Figure 8
Alloy - maximum operating pressure vs.
temperature for ANSI classification.
Configuration
Barksdale’s LevelSite® is a unique
system that can be custom designed
for many types of applications, from a
stand-alone, no-power-required level
Figure 7
indicator to a fully-integrated electronic
component within a process control
system. It can be supplied with process connections located for
any of the four standard patterns: top/bottom, top/side, side/
side, or side/bottom (See Figure 7). For applications where tankside mounting of the LevelSite is not practical or desired, top
mounted versions are available. Liquid interface configurations
require three process connections (See Figure 7).
Material
Pressure/temperature performance parameters for LevelSite
housing constructed of PVC, PP or PVDF are specified in the
chart. Please consult the factory with pressures/temperatures
requiring other materials.
Figure 9
Engineered plastic - maximum operating pressure vs. temperature
Quality
Quality and dependability are built into every Barksdale
LevelSite. As a registered ISO 9001 manufacturer, Barksdale
meets the most demanding international standards. LevelSite®
can be certified to ASME, ANSI, DIN, BSP and other codes.
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LevelSite® Supplemental Guide
Operating Instructions
General Installation
LevelSite®s are measuring instruments and must be properly
treated as such. Make sure that all parts are available and the
connecting flanges on the tank correspond to those on the
indicator. The float and limit switches (if applicable) are enclosed
in a separate box. Remove the bottom connection flange (1) of
the float chamber and insert the float with the top uppermost.
Replace the bottom flange with the gasket, fixing it to the
chamber by tightening all the bolts securely. The LevelSite®
must be raised slowly and carefully so that the float is not
damaged by severe impact.
connector on the LevelSite®. If the transmitter’s probe spans
the entire measuring range (center-to-center of the process
connections), the probe will be marked to show the measuring
range. Electrical Connections: Ground the transmitter’s
housing if necessary. The cable length may be up to 3 miles.
The transmitter is designed to be maintenance-free and is not
field-serviceable. If the unit is not operating properly, replace
the entire unit. For more information, refer back to “Tank Level
Indicating Transmitter”.
Mechanical Installation
It is essential to ensure that the flanges on the tank are
accurately aligned with the flanges on the LevelSite®. Nonalignment of the flanges causes distortion of the float chamber
(2) with the possibility that the float (3) will stick. The Levelsite®
must always be mounted vertically. Before commissioning, the
flags in the flag assembly (4) must be aligned by means of a
magnet so that they all show the color white (polycarbonate) or
silver (aluminum). NOTE: It is essential for all flange bolts, the
vent-plug (5) and the drain-plug (6) to be fully tightened.
Electrical Installation
The electrical limit switches (7) may be attached at any point
in the range on the indicator bar by means of a stainless steel
clip. Ensure that the stainless steel clips are installed under the
flag assembly. The maximum electrical switching capacity is
specified on the nameplate of the limit switch (7) and must not
be exceeded. IMPORTANT: The operation of the LevelSite® is
based on the magnetic field principle. Ferrous strips, clamps, or
screws must not be used.
Commissioning
LevelSite®s are always application specific. The most important
technical data such as pressure and temperature limits are
specified accurately on the nameplate (8). However, the sales
drawing for the model number referenced on the nameplate is
specific and detailed to the application and is the governing
specification document. Before commissioning, a check must be
made to ensure that the technical data shown on the nameplate
corresponds exactly with the plant requirements. NOTE: Test
pressure and test temperature of the plant must NOT exceed the
specifications.
Figure 2
Typical System
Tank Level Indicator (TLI) Installation
The transmitter is installed on the side of the LevelSite® housing,
utilizing stainless steel clips, with the transmitter’s probe along
the housing. The transmitter may be used in addition to a visual
indicator (rotating flag assembly) to provide electronic monitoring
of fluid level. If the transmitter is used with a flag assembly, it
may be necessary to slide the transmitter’s clamps under the
flag assembly. The transmitter is supplied with a mark on its
probe. This mark must line-up with the centerline of the process
3211 Fruitland Avenue • Los Angeles, CA 90058 • 800-835-1060 • Fax: 323-589-3463 • www.barksdale.com
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See Barksdale’s Standard Conditions of Sale • Specifications are subject to modification at any time • Bulletin #L0018-D • 02/08 • ©2008 • Printed in the U.S.A.