PSC 101 - Voltage Proportional to Resistance

Pius Voltage
Plus Sense
To
low
side
of
R.
Power Supply output
Neg. Voltage
Go) 41
(50) 51 52) 53 5511156. 1571 587 59
е
43 444) 45 46 47 48 (>)
Neg. Sense
FIGURE 4-2
4.3
VOLTAGE
PROPORTIONAL
TO
RESISTANCE
Voltage
proportional
to
an
external
resistance
value:
Jumper
between
15
and
16,
17
and
18,
40
and
50,
42 and 52, 44 and 54; connect external resistor between 47 and 48; see Figure 4-3.
The
external
resistance
is
connected
between
Pin
47
and
the
negative
supply
voltage;
¡.e.,
Pin
48
for
front
panel
operation.
The
connection
from
the
extemal
resistance
to
the
negative
supply
voltage
is
the
(-)
sense
lead.
The
output
voltage
will
change
according
to
the
value
of
external
resistance
used
as
shown
below:
MOD
101
`
MOD
102
|
MOD
103
0.5k
ohms/volt
1.25k
ohms/volt
2
5k
ohms/volt
The
accuracy
of
the
output
voltage
versus
resistance
is+10%.
Greater
accuracy
(+1%)
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-23
on
the
first
plug-in
printed
circuit
board
for
the
absolute
voltage
required.
If
a
switch
is
used
to
select
external
resistance
values,
а
make-before-break
switch
should
be
used.
If
the
resistor
is
momentarily
removed
from
the
circuit,
the
output
of
the
supply
will
increase,
momentarily,
to
its
maximum
output
voltage.
In
order
to
minimize
noise
pickup
in
the
leads
to
the
el
resistor,
the
leads
should
be
twisted
or
shielded.
The
low
side
of
the
power
supply
out-
put
should
be
connected
to
ground.
To low side of (DEL
Power Supply output —
(а or
Lead going to No. 48 is (-)
he:
PER:
А
Neg.
sense
lead
(in
this
configuration)
Go) з (2) s
FIGURE 4-3