HP 3400A Service Manual

Operating
Instructions
Model
3400A
b. Set RANGE switch (5) to 300 VOLTS position.
When measuring an ac signal superimposed on a DC level, always
set the range switch to the 300 volt position. A high voltage tran-
sient due to the application of a DC voltage will damage the input
circuitry.
c. Connect test lead to point to be measured.
d. Rotate RANGE switch counterclockwise until meter (1) indicates on upper two thirds
of scale.
3-9. APPLICATIONS
3-10.
The
Model
3400A
can
be
used
in
conjunction
with
other
test
instruments
to
measure
the
rms
value
of
ac
signal
with
a
dc
component,
measure
rms
current
and
act
as
an
rms
ac-to-
dc
converter.
For
additional
informatidn
on
special
applications,
contact
your -hp-
Sales
and
Service
Office.
3-11. RMS Value Of AC Signals With DC Component
3-12.
Since
the
3400A
is
an
ac
device
it
will
measure
only
the
rms
value
of
the
ac
component.
If
it
is
necessary
to
include
the
mms
value
of
the
dc
component
when
measuring
a
signal
use
an
-hp-
Model
3468A
Digital
Multimeter
to
measure
the
dc
component.
Substitute
the
reading
from
the
Model
3468A
and
Model
3400A
in
the
following
formula:
The
ac
signal
(up
to
800V
peak)
may
be
superimposed
on
a
dc
level
of
up
to
600
V.
mms =/ Sacer + Sae-
3-13. RMS Current
3-14. To measure rms current, use an -hp- Model 456A AC Current Probe. This probe clips
around the current conductor and provides an output voltage that is proportional to the cur-
rent
being
measured.
Using
this
method,
rms.currents
of
one
milliampere
to
one
ampere
can
be measured.
3-15. RMS AC-To-DC Converter
3-16.
Since
the
Model
3400A
is
provided
with
a
dc
output
(10,
Figure
3-1)
which
is
propor-
tional
to
the
meter
deflection,
it
can
be
used
as
a
linear
rms
ac
to
de
converter.
The
dc
output
can
be
used
to
drive
an
-hp-
Model
3468A
Digital
Multimeter
for
high
resolution
measurements
and/or
an
-hp-
Model
680
Strip
Chart
Recorder.
External
loading
does
not
affect
the
meter
accuracy
so
that
both
the
meter
and
dc
output
can
be
used
simultaneously.
A
plug
for
DC
OUT
jack
may
be
purchased
under
-hp-
Part
No.
1251-0067.
3-2

HP 3400A Specifications

General

Brand	HP
Model	3400A
Category	Measuring Instruments
Language	English