LFE 2000 Series - Page 96

9.1
q')
958-3
I
REV
SECTION
9
-
SERVICE
&
REPAIR
CHANGING/ADDI
NG
COMPONENTS
The
rnodification
of the
ppnted
circuit
boards
in
the
series
2000
controllers
requires
that
certain
precautions
be
taken
in
the
removal/additlon
of
components'
The use
of
a
low
wattate
lron
with
an
appropriate
tip
taking
care
not
to
expose
the
circuit
board
to unnecessary
heat
is
highly
recommended.
The
use
of
desoldering
aids
such as
vacuum
type
tools
and
"Solder-l^Iick"
for
the
rernoving
and
cleaning
of
circuit
board
holes
should
be
performed
prior
to
the
installation
of
new
cornponents'
EPROM
REPLACEMENT
(U-2
CPU
B0ARD)
(See
Note
I
)
The EPROM
rs
a
digital
memory
device
that
permanently
stores
instructions
and
informatton
protramrned
into
it
at
the
factory.
This
device
(U-2
on
the
CPU
board)
rs
socket
mounted
and
can
be removed
with
the
proper
IC
extraction
tool'
Because
of
the hazard
of
static
discharte
when
handling
MOS
integrated
crrcuits,
special
precautions
must
be
taken
in
the
work
area
to
prevent static
charge
frolrr
causinB
device
failures.
Refer
to MOS
STATIC
DISCHARGE
HANDLING
PRECAIJTIONS
(section
1.13).
The
EPROM
can
be replaced
if
recluires
a
new
program.
A
factory.
Each EPROM
ordered
frorn
the
factory
will
will
lndi.cate
the following:
Drfferent
nunbered
EPR0MS
sane
part
number
but
interchangeable.
The standard
EPROMs
used
for
table
at
the beginning
of Sect
a failure
should
occur,
or if
a special
applrcatlon
new
EpROM
can
be
ordered
by
the
MoD
CENTER
from
the
PART NUMBER
1685_(X)
have
mounted
to its
top
surface
a
label
that
REVISION
(Letter)
DATF.
This
label is
a neans
of identrfying
the
program
configurations
of the
EPROM.
Contact
the factory
for details
on
part
numbers
not
shown
in
this
manual.
tJhen replacing
the
EPRQM rn
the socket
be sure
that
it
j-s
correctly
oriented
and
then
flrmiy
pressed
into
its socket.
The
controller
must
now
be cornpletely
recalibrated
and tuned
following
the
procedure
in
the
appllcable
sections.
After
replacement
of
an EPROM,
the remote
possibility exists
that.
the controller
wjll
not function
correctly.
Thls w111
be
evident
by
the
irregular
indication
on
the
display
and
where
norrnal operation
cannot
be
performed
by the
keypad
controls.
Contact
the
factory for
help in
these
instances.
:!*
NOTE
1
-:':'
ARE
NOT INTERCHANGEABLE.
EPROMS
different
revision
letter
and
the
rnodels
covered
ion
6.
by
this
manual
with the
date
are
are,
I isted
in
the
-89-
LFE
Instruments
Divlslon