HP 6296A - Page 45

5-44
CONSTANT
VOLTAGE
PROGRAMMING CURRENT
5-45
To
calibrate
the
constant
voltage
programming
current,
proceed
as
follows:
a.
Connect
a
0.
l
%
,
20
watt
resistor
between
terminals
-S
and
A4
on
rear
barrier
strip.
Resistor
value
to
be
as
follows:
Model
6282A 6285A 6286A .6290A 6291A 6296A
Res.
2K
4K
4K
SK
BK
l
8K
b.
Disconnect
jumper
between
A3
and
A4
on
rear
terminal
barrier
strip.
c.
Connect
a
decade
resistance
in
place
of
R806.
d.
Connect
a
differential
voltmeter
between
+S
and
-S
and
turn
on
supply.
e.
Adjust
decade
resistance
box
so
that
dif-
ferential
voltmeter
indicates
maximum
rated
output
voltage
within
the
following
tolerances:
Model
6282A 6285A 6286A 6290A 6291A 6296A
Tol.(Vdc)
:0.2
::i:0.4
::t.:0.4
::t.:0.8
:0.8
::i:l.2
f.
Replace
decade
resistance
with
resistor
of
appropriate
value
in
R806
position.
5-46
CONSTANT
CURRENT
PROGRAMMING
CURRENT
5-47
To
calibrate
the
constant
current
programming
current,
proceed
as
follows:
a.
Connect
power
supply
as
shown
in
Fig.
5-4.
b.
Remove
strap
between
A6
and
A7
(leaving
A7
and
AS
jumpered).
c.
Connect
a
O.
1 %
,
1/2
watt
resistor
be-
tween
Al
and
A7.
Resistor
value
is
l!V. (1.
SKt.
for
Models
6290A
and
6296A).
d.
Connect
decade
resistance
box
in
place
of
R808.
e.
Set
METER
switch
to
highest
current
range
and
turn
on
supply.
f.
Adjust
the
decade
resistance
so
that
the
differential
voltmeter
indicates
1.
0
::1:
O.
02Vdc.
g.
Replace
decade
resistance
with
appro-
priate
value
resistor
in
R808
position.
5-48
OVERVOLtAGE
TRIP
5-49
To
adjust
the
overvoltage
trip
point,
proceed
as
follows:
a.
Connect
differential
voltmeter
acres
s
+S
and
-S
terminals
of
supply.
b.
Rotate
VOLTAGE
controls
fully
clockwise.
c.
Turn
on
unit.
Differential
voltmeter
should
read
20%
above
maximum
rated
output
volt-
age
within
:!:5%.
d.
If
it
does
not,
turn
off
supply
and
connect
decade
resistance
across
R60S
in
place
of
R604.
e.
Adjust
decade
resistance
until
differential
voltmeter
reads
that
indicated
in
step
c.
NOTE
The
+15.4V
reference
voltage
must
be
kept
within
::i:0.5Vdc
when
ad-
justing
the
decade
resistance
box.
5-14
f.
Replace
decade
resistance
With
r•esistor
of
appropriate
value
in
R604
position.
5-50
TRANSIENT
RECOVERY
TIME
S-51 To
adjust
the
transient
response,
proceed
a.
follows:
a.
Connect
test
setup
as
shown
in
Figure
5-7.
b.
Repeat
steps
a
through
e
as
outlined
in
Paragraph
5-19.
c.
Adjust
R307
so
that
the
transient
response
is
as
shown
in
Figure
5-8.
5-52
PREREGULATOR
TRACKING
(60Hz OPERATION)
5-53
To
adjust
the
preregulator
control
circ:uit
with
a
60Hz
ac
input,
proceed
as
follows:
a.
Connect
proper
load
resistor
acroiss
out-
put
terminals
of
supply.
Resistance
value
1to
be
as
follows:
MQQfil.
6282A 6285A 6286A 6290A 6291A 6296A
Res.
l.n.
4n.
2.n.
l
3n.
8.n.
2
o.,..
b.
Connect
DC
voltmeter
between
TP27
and
TP90
(across
series
regulator).
c.
Turn
on
supply
and
adjust
VOLTAGIE
con-
trols
for maximum
rated
output
voltage.
d.
Adjust
i71
l
so
that
DC
voltmeter
reads
3
::i:
O.
2Vdc.
5-54
PREREGUIATOR
TRACKING
(SOHz
OPERATION)
5-55
To
adjust
the
preregulatorcontrol
circuitwhe.n
the
ac
input
is
from a
SOHz
source,
proceed
as
follows:
a.
Connect
load
resistor
across
rear
output
terminal
of
supply.
Resistor
value
to
be
as
follows:
Model
6282A 6285A 6286A
6290A 6291A 6296A
Res.
l.n.
4n
2.n.
l
3n.
Sn
20.n.
b.
Connect
o.scilloscope
(de
coupled)
across
series
regulator,
T.
P.
27
to
T.
P. 90.
c.
Disconnect
R709
in
the
SCR
control
circuit,
and
connect
decade
resistance
box
in
its
place.
d.
Rotate
CURRENT
controls
fully
clockwise
and
turn
on
supply.
e.
Decrease
resistance
of
decade
resistance
from normal
value
of
R709
until
sawtooth
waveform
on
oscilloscope
is
symmetrical
(amplitude
of
SOH-z
sawtooth
waves
are
equal).
f.
Replace
decade
resistance
box
with
ap-
propriate
value
resistor
in
R709
position.
g.
Adjust
ramp
potentiometer
R711
for
3.SVdc
drop
across
series
regulator.
h.
If
3.S
volts
cannot
be
obtained,
remove
R712 (in
series
with
R711)
and
connect
the
decade
resistance
box
in
its
place.
i.
Increase
value
of
decade
resistance
box
from
normal
value
of
R712
until
3.SVdc
drop
is
ob-
tained
across
series
regulator.
j.
Remove
decade
resistance
and
con.nect
new
resistance
value
in
R712
position.
•