HP Lab Series User Manual

Table
S-1.
Test
Equipment Required (Continued)
TYPE
REQUIRED
CHARACTERISTICS
Resistor
Value:
See
Paragraph
5-78.
:1::0.1%,
5
Watts.
Resistor
Value:
See
Paragraph
5-81.
:1::0.1%,
5
Watts.
Capacitor
SOOµf,
SOWVdc.
Decade
Range:
0-lSOK
{min.}.
Accuracy:
Resistance
0~1%
plus
1 ohm.
Make-before-
Box
break
contacts.
NOTE
A
sat1$factory
substitute
for a
differen-
tial
voltmeter
is
to
arrange
a
reference
voltage
source
and
null
detector
as
shoWn
in
Figure
5-1.
The
reference
voltage
source
is
adjusted
so
that
the
voltage
difference
between
the
supply
being
measured
and
the
reference
volt-
age
will
have
the
required
resolution
for
the
measurement
being
made. The
voltage
difference
will
be
a
function
of
the
null
detector
that
is
used.
Examples
of
satisfactory
null
detectors
are:
HP
419A
null
detector,
a
de
coupled
oscil-
loscope
utilizing
differential
input,
or
a
50mV
meter movement
with
a
100
division
scale.
For
the
latter,
a
2mV
change
in
voltage
will
result
in
a
meter
deflection
of four
divisions.
POWER
SUPPLY
UNDER
TEST
REFERENCE
VOL1'AGE
SOURCE
I.DAD
NULL
DETECTOR
+
0
Figure
5-1.
Differential
Voltmeter
Substitute,
Test
Setup
S-2
USE
RECOMMENDED
MODEL
Calibrate
programming
----
CWTent
Calibrate
programming
----
current
Measure
impedancs
---
Measure programming
co-
---
efficients
------cCAUTION-N-----
Care
must
be
exercised
when
using
an
electronic
null
detector
in
which
one
input terminal
is
grounded
to
a void
ground loops and
circulating
currents.
5-5
PERFORMANCE
TEST
5-6
The following
test
can
be
used
as
an
incoming
inspection
check
and
appropriate
portions
of
the
test
can
be
repeated
either
to
check
the
operation
of
the
instrument
after
repaks
or
for
periodic
main-
tenance
tests.
The
tests
are
performed
using
a 115
Vac 60Hz,
single
phase
input power
source.
If
the
correct
result
is
not
obtained for a
particular
check,
do
not
adjust
any
controls;
proceed
to
trouble-
shooting
(Paragraph
5-51).
5-7
CONSTANT
VOLTAGE
TESTS
5-8
The measuring
device
must be
connected
across
the
sensing
leads
of
the
supply
or
as
close
to
the
output terminals
as
possible
when
measuring
the
output impedance,
transient
response;
regula-
tion,
or
ripple
of
the
power supply
in
order
to
achieve
valid
measurements. A
measurement
made
across
the
load
includes
the.impedance
of
the
leads
to
the
load
and
such
lead
lengths
can
easily
have
an
impedance
several
orders of magnitude
greater
than
the
supply impedance,
thus
invalidating
the
measurement.
5-9
The monitoring
device
should.
be
co~ected
to
the
+S
and
..;S
terminals
(see
Figure 3-2} or
as
shown in Figure
5-2.
The performance
characteris-
tics
should never
be
measured on
the
front
terminals
if
the
load
is
connected
across
the
rear
terminals.
Note
that
when measurements are
made
at
the
front
•
•
terminals,
the
monitoring
leads
are
connected
at
A,
•
not
B,
as
shown
in
Figure
5-2.
Failure
to
connect
_

HP Lab Series Specifications

General

Brand	HP
Model	Lab Series
Category	Power Supply
Language	English