Fluke 893A - Page 51

«yaA
an
insulated tool, for
a meter indication of
zero-
center
±1 major
division.
The stray capacity
compensator
is located between front
panel and
chassis of the instrument along
with R12. This
adjustment is
accessible from the top of the
Model
893A
and from the bottom of the Model 893AR.
CAUTION’
The 100
VAC
input voltage
is present on the
stray capacity compensator.
d. Set the Readout dials
to 01. 0
00
e.
Apply
a
calibrated one volt ac signal
at 400 Hz
be-
tween
the HI
and
LO
INPUT terminals. A
meter
indication of zero-center
±
one small
division should
be obtained.
f.
Apply a
calibrated one volt ac signal at 50 kHz
between the
HI
and LO INPUT terminals
and adjust
A7C15 for the
same meter indication obtained
in
step
e.
g.
Repeat steps
c
through
f until the specified
results
are
obtained.
h.
Set
the
Readout
dials
to 10 0.
0 (W and perform the
checks indicated in Figure
4-16.
MODEL 893 AC
INPUT VOLTAGE
METER
INDICATION
(±
MAJOR
DIVISIONS)
100
vac, 10 kHz
100 vac, 100 kHz
100 vac, 20 Hz
0
±1.5
m. d.
±2
m. d.'“
0
±7
m. d.
— 1 Ml 1
'
Figure 4-16. 100
VOLT RANGE CHECKS
1.
Place
the RANGE
switch to its
10 volt
range
position
and set
NULL SENS
TO .001.
j.
Apply
a calibrated 10 volt ac signal at 400 Hz
between
the HI
and
LO INPUT
terminals and
adjust A7R33 for
a meter deflection of zero-center
±1/2
major
divisions.
k.
Apply
a calibrated 10 volt ac signal at 50 kHz
between
the HI and LO INPUT
terminals and adjust A7C21
for
a
meter indication of zero-center
±1/2
major
divisions.
1. Perform the
10 volt range checks indicated in
Fig-
ure 4-17, observing tliat the specified
results are
obtained.
MODEL
893 AC
INPUT’ VOLTAGE
METER INDICATION
(±
MAJOR
DIVISIONS)
10
vac, 10 kHz
10 vac,
100 kHz
10 vac, 20 Hz
0
± 1.5
m. d.
0
±
2 m. d.
*
0
±7m. d..
*NULL SENSE
TO.
1
Figure
4-17.
10 VOLT RANGE CHECKS
m. Place the
RANGE
switch to
its
1 volt
ranee
position
and set
NULL
SENS TO
.001
.
n.
Apply
a
calibrated
one volt ac signal
at 400 Hz
be-
tween
the
HI
and LO INPUT
terminals and
adjust
A7R35
for
a
meter indication
of zero-center
±1/2
major divisions.
o. Apply
a calibrated one volt
ac signal at 50
kHz be-
tween the HI and LO INPUT
terminals and adjust
A7C22 for
a meter indication
of zero-center
±1/2
major divisions.
p.
Perform the
one volt range
checks
indicated in
Fig-
ure
4-18, observing that
the
specified
results are
obtained.
MODEL
893
AC
INPUT
VOLTAGE
METER
INDICATION
(±
MAJOR
DIVISIONS)
1
vac,
10 kHz'
1
vac,
100
kHz
1
vac,
20 Hz
0
±1.5 m.d.
0
±2.5 m.
d.*
0
±7 m. d.
*
NULL SENS
to
.
01
Figure 4-18. 1
VOLT RANGE
CHECKS
q.
Set the Pteadout dials
to . 10000
and perform tlie
range
checks contained in
Figure
4-19, observing tliat
the
specified results are obtained.
MODEL 893
AC
INPUT
VOLTAGE
METER
INDICATION
(±
SMALL
DIVISIONS)
0.1
vac, 400
Hz
0. 1 vac, 50
kHz
0
±1
s.d.
0
±3 s.d.
Figure
4-19.
1
VOLT RANGE
(0. 1 SCALE) CHECKS
r. Set
the
Readout dials to
.
00100
and perform
the
range
checks
contained in
Figure
4-20,
observing
that
the
specified
results
are obtained.
MODEL 893 AC
INPUT VOLTAGE
METER
INDICATION
(±
SMALL
DIVISIONS)
0.001 vac, 50
kHz
0.001 vac, 400
Hz
0
±1 s,
d.
0
±1/2
s.d.
Figure 4-20.
1 VOLT RANGE (O.OOi
SCALE) CHECKS
s. Place the RANGE
switch
to its
1000 volt
range po-
sition and
set the Readout
dials
to
500. 00.
t. Apply a
calibrated 500
volt ac
signal
at 400 Hz be-
tween the HI
and LO INPUT
terminals
and adjust
4-17
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