Victor 98A, Руководство пользователя

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Warning Warning Warning
Warning
  

Do Do Do
Do
not not not
not
apply apply apply
apply
more more more
more
than than than
than
DC DC DC
DC
1000 1000 1000
1000
V V V
V
or or or
or
AC AC AC
AC
750 750 750
750
rms rms rms
rms
voltage; voltage; voltage;
voltage;
the the the
the
meter meter meter
meter
will will will
will
possibl possibl possibl
possibl
eee
e
be be be
be
damaged damaged damaged
damaged
though though though
though
the the the
the
value value value
value
could could could
could
be be be
be
displayed. displayed. displayed.
displayed.




Indicator Indicator Indicator
Indicator
“ “ “
“
” is on on on
on
display display display
display
for for for
for
safety safety safety
safety
note note note
note
when when when
when
30 30 30
30
V V V
V
ac ac ac
ac
and/or and/or and/or
and/or
dc dc dc
dc
voltage voltage voltage
voltage
present present present
present
at at at
at
the the the
the
input input input
input
terminals terminals terminals
terminals

The
The
The
The
meter
meter
meter
meter
beeps
beeps
beeps
beeps
constantly
constantly
constantly
constantly
if
if
if
if
the
the
the
the
input
input
input
input
voltage
voltage
voltage
voltage
is
is
is
is
more
more
more
more
than
than
than
than
AC
AC
AC
AC
750V
750V
750V
750V
rms,
rms,
rms,
rms,
which
which
which
which
is
is
is
is
over
over
over
over
the
the
the
the
meter
meter
meter
meter
’’’
’
sss
s
range.
range.
range.
range.
dB
dB
dB
dB
m
m
m
m
Measurements
Measurements
Measurements
Measurements
in
in
in
in
AC
AC
AC
AC
Volts
Volts
Volts
Volts
Functions
Functions
Functions
Functions
(See
(See
(See
(See
Figure
Figure
Figure
Figure
3-2)
3-2)
3-2)
3-2)
The ac volts functions allow you to display readings as deviations in dB (decibels) above or below an established level.
Set up dB measurements with the following procedure:
1. Make an ac volt measurement to be used as a reference point.
2. Press
to select dB. The dBm value appears in the primary display and the ac volts reading appears in the secondary
display.
3. Press
again to turn dB off.
Normally, dB is measured as dBm, which is a measure of decibels relative to 1 milliwatt. The meter assumes a resistance of 600
 in making this calculation. This resistance can be set for any value for50Ω
，
75Ω
，
93Ω
，
100Ω
，
150Ω
，
300Ω
，
600Ω
，
800Ω
，
1200Ω
，
2400Ω, using the meter’s setup capabilities (see Chapter 5.) to change the resistance.
Figure 3-2.dBm Measurements
Note Note Note
Note
If If If
If
dBm dBm dBm
dBm
is is is
is
displayed, displayed, displayed,
displayed,
check check check
check
that that that
that
the the the
the
reference reference reference
reference
resistance resistance resistance
resistance
value value value
value
closely closely closely
closely
matches matches matches
matches
the the the
the
impedance impedance impedance
impedance
of of of
of
the the the
the
system system system
system
being being being
being
measured. measured. measured.
measured.
dB is calculated with the following formula:
10
20 log
Vx
dBm
Vr
 

 
 
＝
 For dBm, Vr is the voltage across the reference resistance at 1mW. For example, Vr would be 0.7746 V with a 600-
Ω reference resistance.
Measuring Measuring Measuring
Measuring
DC DC DC
DC
Voltage Voltage Voltage
Voltage
(((
(
See See See
See
Figure Figure Figure
Figure
3-3) 3-3) 3-3)
3-3)
1. Set the rotary switch to position, and “DC”, “V” will be on display.
2. Insert the black lead into “ COM COM COM
COM
” terminal, and the red lead to into the “ Ω Ω Ω
Ω
V V V
V
” terminal.
3. Connect the leads to the tested power.
4. Read the measuring results from the screen.