LFE 2000 Series - Page 36

958-31
REV.
B
3.4
MODIFICATION
FROM
THERMOCOUPLE
INPUT
TO
DC VOLTAGE
INPUT
Remove
the
rnput/output
(I/o)
board
from
the electronic
assenrbly
per
instruction
1n
Section
l.l0
and
rnake
the following
changes.
Refer
to
the
DC
VOLTAGE
INPUT
RANGE
RESISTORS chart
(Table
3-l
)
for values
setected
for
standard
ranges.
The values
for
the
attenuator
resistor
Rl
&
R2 are based
on a
full
range
dc
i,nput
of
50
mV at
the
junction
of Rl &
R2.
I
.
REMOVE
resistors
R3, R5.
2,
OPEN
Jl5
if
noted
in
Table 3-1.
(NOTE:
Make
sure
that the
entire length
of the
foil
bridge
between
pads
is removed
to achieve
proper
spaclng.
3.
ADD
resi-stors
Rl
and R2
(see
Table
3-l
)
.
4,
REPLACE
capacitors
C4 and C5
as
listed in Table
3-1.
5.
SHORT
J35
solder
bridge
(on
conponent
side).
ALTERNATIVE:
0n
older PCBrs,
ADD a
wire
jumper
from the
feed
through at
termrnal
G to
the
feed through
at
terrnlnal F
(GND).
6,
REMOVE
the
Cold
Junction
Compensating
Resistor
assembly from
the
rear
termrnals
of
the
controller
case
(terminals
F
& G) for older controllers
or
remove
the
compensatrng
resistor
(CJC1)
and
its support from
the I/0 board
of newer
controllers.
DI
VOLTAGI
I|.IPU]
R1
(tTT
P/|,l)
R2
(LFT
PiN)
J15
REPIACI C4 REPIACI C5
RANGI
SOIDIR BRIDGT
(tFT
P/|.l)
(LFI
P/|1)
0 to
50 mV
t.l0N[
N0|'1i
S|I0RTED
N0 |.i0
0 to
100 mV 499K-1?
(1849-4993)
499K-1?
(1849-4993)
0PEN
tuF
(305-124)
Z,?uF
(105-1BB)
0 to 500 mV 750K-lv;
(1849-i54)
84,5K-1?
(1849-8452)
0PEN
,
2,2uF(105-1BB) 2,2ur
(305-1BB)
0 to 1.0 V i50|(-1?
(1849-754)
39.2K-12
(1849-3922)
0ptN
:
2,2uF(305-188) N0
0
t0 5,0 v 750l(-1?
(1849-754)
l,5K-p"
(1849-752)
0pt|.l
l'{0
|l0
0 to
10
V
750K-1?
(1849-754)
3.74K-1?
(1849-3741)
0PtN N0 |l0
0 to 50 V 750K-i?
(1849-754)
7504-1?
(1849-751)
0PtN N0 N0
0
to 100
v
750|(-1?
(1849-754)
3654-1?
(1849-3650)
0PtN f'10 |i0
Table
3-l
DC
VOLTAGE
INPUT RANGE RESIST0RS
-29-
LFE
Instruments Drvision