Noisy Resistance Measurements; Measuring Capacitance - Fluke 8010A User Manual

NOTE
In the
conductance
range, there
is
normally
a small
residual
reading with open
test leads.
To ensure
accurate measurements, connect clean
test
leads to
the
meter
and
(with the leads
open) read
the
residual leakage
in
nanosiemens. Correct
subse-
quent measurements by
using the Relative
mode
(REL)
to 2ero the display,
which
subtracts the
residual
from
the readings.
Diode leakage
tests require that the
diode
junction
be reverse-
biased
when
being
measured. To do
this,
connect
the
anode
of
the diode
to
the
COM
input terminal
and
the
cathode
(ring) of
thediodetothe
VQ-»+- input terminal.
Leakage
at
the
test volt-
age
being applied
can
then
be
read
in
terms
of
conductance.
High-voltage, stacked diode,
assemblies can
usually
be
tested
for
forward
and
reverse resistance
changes
using
conduc-
tance.
These assemblies
typically
have such high forward
volt-
age
drops that the
diode
test
or resistance
modes
cannot
test
them.
Noisy Resistance
Measurements
Your Fluke meter
is
designed
to tolerate
up
to
several volts of
ac
noise.
Noise appears as changing
numbers on
the
digital
display
and as an
oscillating
analog
display.
Changing
the
APPLICATIONS
Measuring Capacitance
range
may
reduce
the
noise.
To smooth
out the
effect of
noise
on your readings, enter the
MIN
MAX
Recording
mode
and
scroll to the
average
reading.
Measuring Capacitance
CAUTION
Turn
off
power and
discharge
the capacitor
before attempting a capacitance measurement.
Use
the
(
V
)
function to
confirm
that
the capaci-
tor
is
discharged.
The
meter measures capacitance by charging
the capacitor
with a
known
current,
measuring
the
resultant voltage,
and
calculating
the capacitance.
The measurement
takes
about
1
second
per
range (push
button
responses
also take about
1
second).
The
capacitor charge
can be up
to
1.2V.
For measuring
capacitor values up
to
5.8/uF,
turn the rotary
switch to 'Win
-it-,
press
the
BLUE
button,
and connect
the
test
leads
to
the
capacitor.
The
meter
will
select the proper
range
automatically.
Each measurement
takes
about
1
second
per range.
Wh
en
mak
ing
repeated
measurements
of
similar values,
press
QwqQ
to manually select the proper
range
and
to
speed up subsequent measurements.
For
capacitors
less
than 5
nF
or
in
noisy environments, use
short
test
leads or
a
test fixture
(1
nF
-
1000
pF).
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