It
is
suggested
that
the
Model
L80
be
installed
in
an
external
cage
for
maintenance
and
testing
purposes.
A
recommended
piping
system
for
mounting
an
external
cage
to
a
vessel
is
shown
in
Figure
2.
The
valves
above
and
below
the
cage
are
required
for
testing
and
maintenance
purposes.
If
a
cage
with
weld
connections
is
used,
the
level
switch
should
be
removed
from
the
cage
before
welding.
This
will
prevent
weld
sparks
form
damaging
the
displacer
assembly.
Remove
the
switch
from
the
cage
as
per
instructions
in
paragraphs
5.2.1
through
5.2.2
of
the
FULL
DISASSEMBLY
section
of
this
manual.
After
welding
install
the
level
switch
as
per
instructions
in
Section
3.2
INSTALLING
SWITCH
IN
CAGE.
If
the
cage
has
threaded
or
flanged
process
connections,
the
level
switch
does
not
have
to
be
removed
before
mounting
the
switch
to
the
vessel.
Cages
with
1"
NPT
process
connections
may
be
installed
on
the
vessel
with
1",
¾",
or
½"
O.D.
piping.
CAUTION:
The
pressure
rating
of
all
pipe,
valve,
and
pipe
fittings
must
meet
or
exceed
the
working
pressure
of
the
vessel
they
are
to
be
installed
on.
Adequate
support
for
long
pipe
runs
should
be
provided
to
prevent
excessive
vibrations
of
the
level
switch.
It
is
recommended
that
external
cages
be
installed
with
the
process
connections
as
close
to
vertical
and
the
cage
length
as
close
to
horizontal
as
possible.
This
will
insure
the
proper
fluid
flow
through
the
cage.
3.2
LEVEL
SWITCH
INSTALLATION
Before
installing
a
level
switch
into
an
external
cage
or
mating
flange
verify
that
the
level
switch
is
configured
for
the
operation
mode
required
(i.e.
direct
(low)
or
reverse
(high)
action).
See
Section
4.0
CHANGING
MODE
OF
OPERATION
and
Figure
5.
NOTE:
When
direct
mounting
a
level
switch
to
a
tank
or
vessel
verify
that
the
back
of
the
displacer
assembly
will
be
at
least
½"
(13mm)
longer
than
the
2"
connection
it
is
being
installed
into
(See
Figure
4).
TOOL
REQUIRED:
2.125"
open
end
or
suitable
adjustable
wrench
or
pipe
wrench
3.2.1
Clean
any
dirt
or
debris
form
the
2"
NPT
pipe
threads
of
the
switch
and
mating
connection
3.2.2
Apply
Teflon
tape
or
other
tread
sealing
compound
to
the
2"
NPT
threads
on
the
switch
3.2.3
Apply
and
anti
‐
galling
compound
to
the
2"
NPT
female
thread
that
the
switch
is
to
be
installed
into.
3.2.4
Screw
the
switch
into
the
mounting
tread
and
tighten
with
the
wrench.
When
tight,
the
spring
cap
must
be
up
as
shown
in
figure
5.
