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Note:
Note:
Note:
Note:
ℕ
Reading is possible at input voltages above 3V rms, but the
accuracy is not guaranteed.
ℕ
In noisy environment, it is preferable to use shield cable for
measuring small signal.
B)
B)
B)
B) To
To
To
To measure
measure
measure
measure frequency
frequency
frequency
frequency by
by
by
by AC
AC
AC
AC Voltag
Voltag
Voltag
Voltage
e
e
e (or
(or
(or
(or AC
AC
AC
AC Current)
Current)
Current)
Current)
range
range
range
range
ℕ
Set the rotary switch to the desired range (AC Voltage or
AC Current).
ℕ
Connect the black and red test leads to the
COM
COM
COM
COM
and
V
V
V
V
(or
mA
mA
mA
mA
) terminals respectively.
ℕ
Connect the meter to the signal source; then press Hz/%
key.
ℕ
For 5V logic signals (TTL), use the 4Vdc range. For 12V
switching signals in automobiles, use the 40Vdc range.
ℕ
Read the frequency of the AC signal on the display.
ℕ
To make a duty cycle measurement, press the
Hz
Hz
Hz
Hz %
%
%
%
key again.
ℕ
Read the percent of duty cycle on the display.
Note:
Note:
Note:
Note:
ℕ
If the reading is 0.000Hz or is unstable, the input signal may
be below or near the trigger level.
These problems can frequently be fixed by selecting a lower
range, which increases the sensitivity of the meter. In the
DCV function, the lower ranges also have lower trigger
levels.
ℕ
If a reading seems to be a multiple of what you expect, the
input signal may be distorted.
21
Distortion can cause multiple triggering of the frequency
counter. Selecting a higher voltage range might solve this
problem by decreasing the sensitivity of the meter. Also, try
selecting a dc range, which raises the trigger level. In
general, the lowest frequency displayed is the correct one.
3.2.
3.2.
3.2.
3.2.8
8
8
8 Current
Current
Current
Current measurement
measurement
measurement
measurement
To
To
To
To avoid
avoid
avoid
avoid damage
damage
damage
damage to
to
to
to the
the
the
the Meter
Meter
Meter
Meter or
or
or
or injury
injury
injury
injury if
if
if
if the
the
the
the fuse
fuse
fuse
fuse
blows,
blows,
blows,
blows,
never
never
never
never
attempt
attempt
attempt
attempt
an
an
an
an
in-circuit
in-circuit
in-circuit
in-circuit
current
current
current
current
measurement
measurement
measurement
measurement where
where
where
where the
the
the
the open-circuit
open-circuit
open-circuit
open-circuit potential
potential
potential
potential to
to
to
to
earth
earth
earth
earth is
is
is
is greater
greater
greater
greater than
than
than
than 250V.
250V.
250V.
250V.
To
To
To
To avoid
avoid
avoid
avoid damage
damage
damage
damage to
to
to
to the
the
the
the meter,
meter,
meter,
meter, check
check
check
check the
the
the
the meter's
meter's
meter's
meter's
fuse
fuse
fuse
fuse before
before
before
before proceeding.
proceeding.
proceeding.
proceeding. Use
Use
Use
Use the
the
the
the proper
proper
proper
proper terminals,
terminals,
terminals,
terminals,
function,
function,
function,
function, and
and
and
and range
range
range
range for
for
for
for your
your
your
your measurement.
measurement.
measurement.
measurement. Never
Never
Never
Never
place
place
place
place the
the
the
the probes
probes
probes
probes in
in
in
in parallel
parallel
parallel
parallel with
with
with
with a
a
a
a circuit
circuit
circuit
circuit or
or
or
or
component
component
component
component when
when
when
when the
the
the
the leads
leads
leads
leads are
are
are
are plugged
plugged
plugged
plugged into
into
into
into the
the
the
the
current
current
current
current terminals.
terminals.
terminals.
terminals.
The Meter's current ranges are 400.0
µ
A, 4000
µ
A, 40.00mA,
400.0mA, and 10.00A.
To measure current:
1. Turn off power to the circuit. Discharge all high voltage
capacitors.
2. Set the rotary switch to the
µ
A, mA or A range.
3. Press the
SELECT
SELECT
SELECT
SELECT
key to select DCA or ACA measuring
mode.
4. Connect the black test lead to the
COM
COM
COM
COM
terminal and the
red test leads to the mA terminal for a maximum of
400mA. For a maximum of 10A, move the red test lead
to the
10
10
10
10A
A
A
A
terminal.
22