Keithley 153, Инструкция по эксплуатации

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OPERATING INSTRUCTIONS
b.
For
best results with fl
o
a
t
i n g o p
e
r a t
i o
n
,
follow the steps below:
1.
Remove
the sh o r
t
ing link
from
the
LO
or
GND
Post
on the rear
p
a
n
e
l
.
MODEL 153
2.
Connect
the
unknown s o
u r
c
e
to
t h
e
Model
153, connecting the lowest im
p
e
d
a n c e
point
to
the
input
low.
Operate
as described in p
a
r
a
g
r
a
p h
2-4.
Do
not
ground any re­
corders used with
this
operation, since
the
low of the Model 153
output is n
o longer
gr
ou
n d
e
d .
3.
Use
triaxial
cable
and
c o n n
e
c t o r s for floating o p e r a ti o n
.
A
c o
mpl e t e outer shielc
pr
o t ects the operator.
4. Make sure the chassis is grounded. Use the G Post on the rear panel
o
r the grounc
pin o
f
the power c ord .
2-7. RECORDER
OUTPUT.
B.
Mod�l
153 output for
full-scale
meter deflection
on
any range is adjustable from
0
to
il.OS volts at up
to 1
milliampere.
Output polarity is
p
o si
t
i v e
.
Output resistance
is less
than
10
o
h m s
with
the
DC
OUTPUT ADJ
Control
s e t
for
maximum
ou t p
u t
; resistance vari
with the Control
s e
t
t
i
n
g to
7.5
kilohms
maximum.
If the
Model 153
is
used
for
f
l o a t i
n
g
measurements,
do
not g r o
u
n d
the
r
e c
o r
d
e r
connected to the
output.
b.
When
r
e
c o r
d i n
g with the Model
153
use
t
h
e
Keithley
Mo
d e
l
370
R
e
co
r
d
e
r
.
The output
of
the Model
153
is sufficient to drive the Mo d
e
l 370 w
i
t h o u t the use of any r e c
o
r d e r
preamplifiers.
The Model 370
allows
maximum
c
a p a b i l
i
t y of
the
Model
1
5
3
.
It
has 1% line­
arity,
10
chart speeds and c
a
n
float up
to
ISOO
volts off ground. Using t h e Model 370
with
t
h
e Model 153 avoids interface problems which may be
encountered between a m
e
a
s
uri
n
g
instrument and
a
recorder.
c.
To u s e the Model 3 7 0 with the Mode l 153 conne ct the high and l ow binding posts on
t
h
e
Model 153 rear p
a
n
e
l to the
same posts on the Model
370. Do
not
ground the Mode l 370
1f differential measurements
ar
e being made. Adjust the easily accessible Calibration
Control on
the
Model 370 for full-scale recorder deflection.
2-8. INPUT CONNECTIONS.
a. The Model 153
INPUT
Receptacle is a triaxial type; its mating co nn e c t
or
is the
Keithley Mode l 1533. For input
leads
to the Model 153,
Keithley
Instruments, Inc. ,
has
the
Model 1534
Special
Low-Thermal
Triax
cable which can be conne cted directly to the
Mode l 1533 Connector. The Connector is made to accommodate
the 0.145-inch
o u te r diam�ter
of the
Cable.
b. For best connections to the input, use the acc e s s o r y p r o b e s and l
e
a d s describe d in
S
e
c t i on 7. This w i l l
enable
the
Model
153
to be
used under the best conditions.
Other
considerations for
making
sure the Model
153 is pro
p e
r
l
y connected are listed
in the
following paragraphs.
c. carefull y shield the input connection and the source b e i n g measured. Unless the
shielding
is
thorough,
any alteration in the electrostatic field near the input circuitry
will c a u
s
e definite meter disturbances.
8