PSC 101 - Page 17

4.4
4.5
МОПАСЕ PROPORTIONAL TO VOLTAGE REFERENCE
Voltage
proportional
to
an
external
control
voltage:
Jumper
between
18
and
54,
40
and
50,
42
and
52,
48
and
49;
connect
15
and
19
to
(+)
side
of
reference
voltage;
connect
17
to
(-)
side
of
reference
voltage;
see
Figure
4-4.
The
output
voltage
will
change
according
to
the
value
of
external
control
voltage
as
shown
below:
MOD
101
MOD
102
- MOD
103
0.1
volts/volt
0.25
volts/volt
0.4
volts/volt
To
calibrate
the
unit,
apply
the
required
control
voltage
for
full
supply
output
voltage
and
adjust
the
front
panel
voltage
control
knobs
for
the
specified
output
voltage
from
the
supply.
The
input
resis-
tance,
as
seen
by
the
external
control
voltage
source,
is
greater
than
1
megohm.
The
source
resis-
tance
of
the
external
control
voltage
source
should
be
less
than
1k
ohms
to
obtain
the
specified
power
supply
stability.
Precautions
should
be
taken
to
avoid
pickup
in
the
external
leads.
The
low
side
of
the
power
supply
output
should
be
connected
to
ground.
To low side of )
Power
Supply
output
'
Lead going to No. 15 from
(+) plus side of reference supply
is plus sense lead
FIGURE 4-4
CURRENT
PROPORTIONAL
TO
RESISTANCE
Current
proportional
to
an
external
resistance
value:
Jumper
between
15
and
16,
17
and
18,
44
and
54,
48
and
49;
connect
40
and
52
to
one
side
of
resistor
and
19
to
other
side;
see
Figure
4-5.
MOD
101
MOD
102
-
‘MOD
103
5k/amp
2k/amp
1k/amp
The
accuracy
of
the
output
current
versus
resistance
15+10%.
Greater
accuracy
can
be
obtained
by
recalibrating
the
power
supply
internally.
This
is
accomplished
by
connecting
the
desired
resistance
to
the
power
supply
and
adjusting
Pot
R-22
on
the
first
plug-in
printed
circuit
board
for
the
absolute
current
required.
The
output
current
versus
resistance
is
slightly
non-linear,
but
will
vary
less
than
+10%
from
the
best
straight
line
drawn
through
the
response
curve.
Ша
switch
is
used
to
select
ех-
ternal
resistance
values,
a
make-before-break
switch
should
be
used.
If
the
resistor
15
removed
from
the
circuit,
or
too
large
a
value
is
selected,
the
power
supply
will
not
be
short-circuit
current
limited
and
may
be
destroyed.