EasyManuals Logo

HP Lab Series User Manual

HP Lab Series
60 pages
To Next Page IconTo Next Page
To Next Page IconTo Next Page
To Previous Page IconTo Previous Page
To Previous Page IconTo Previous Page
Page #22 background imageLoading...
Page #22 background image
SL.AV£
Figure
3-9.
Auto-Series,
Two and Three
Units
3-39
In
order
to
maintain
the
temperature
coeffi-
cient
and
stability
specifications
of
the
power
sup-
ply,
the
external
resistors
(Rx)
shown
in
Figure
3-9
should
be
stable,
low
noise,
low
temperature
coef-
ficient
{less
than
30ppm
per
degree
centigrade)
re-
sistors.
The
value
of
each
resistor
is
dependant
on
the
maximum
voltage
rating
of
the
"master"
supply.
The
value
of
Rx
ls
this
voltage
divided
by
the
volt-
age
programming
current
of
the
sla11e
supply
(l/Kp
where
Kp
is
the
voltage
programming
coefficient).
The
voltage
contribution
of
the
sla11e
is
determined
by
its
voltage
control
setting,
3-40
When
the
center
tap
of
an
Auto-Series combi-
3-5
nation
is
grounded, coordinated
positive
and
nega-
tive
voltages
result.
This
technique
is
commonly
referred
to
as
"rubber-banding"
and
an
external
ref-
erence
source
may
be
employed
lf
desired.
.Any
change
in
the
internal
or
external
reference
source
(e.g.
drift,
ripple)
will
cause
an
equal
percentage
change
in
the
outputs
of
both
the
master
and
slave
supplies.
This feature
can
be
of
considerable
use
in
analogue
computer
and
other
applications,
where
the
load
requires a
positive
and a
negative
power
supply
and
is
less
susceptible
to
an
output
voltage
change occurring simultaneously
in
both
supplies
than
to
a change
in
either
supply
alone.
3-41
PARALLEL
OPERATION
3-42
Normal Parallel
Connections
(Figure
3-10).
Two
or
more power
supplies
can
be
connected
in
parallel
to
obtain a
total
output
current
greater
than
that
available
from
one power
supply.
The
total
output current
is
the
sum
of
the
output
currents
of
the
individual power
supplies.
The
output
CURRENT
controls
of
each
power
supply
can
be
separately
·
set.
The output voltage
controls
of
one
power
sup-
ply
should
be
set
to
the
desired
output
voltage:
the
other
power supply should
be
set
for
a
slightly
larger
output
VC?ltage.
Tbe supply
set
to
the
lower
output
voltage
will
act
as
a
constant
voltage
source;
the
supply
set
to
the
higher output
will
act
as
a
con-
stant
cuiTent
source,
dropping
its
output
voltage
until
it
equals
that
of
the
other
supply.
The
con-
stant
voltage
source
will
deliver
only
that
fraction
of
its
total
rated
output current
which
is
necessary
to
fulfill
the
total
current demand.
Figure
3-10.
Normal
Parallel
3 -43 Auto-Parallel. The
strapping
patterns
for
Auto-Parallel
operation
of
two
and
three
power
sup-
plies
are
shown
in
Figure
3-11.
Auto-Parallel
oper-
ation
permits
equal
current sharing under
all
load
conditions,
and allows
complete
control
of
output
current
from one master power
supply,
The
output
current
of
each
slave
is
approximately
equal
to
the
master•
s.
Because
the
output
current
control"s
of
each
slave
are
operative.
they
should
be
set
to

Questions and Answers:

Question and Answer IconNeed help?

Do you have a question about the HP Lab Series and is the answer not in the manual?

HP Lab Series Specifications

General IconGeneral
BrandHP
ModelLab Series
CategoryPower Supply
LanguageEnglish

Related product manuals