PSC 101 - Operating Instructions; Normal Front Panel Operation; External Voltage Sense

SECTION 4
OPERATING INSTRUCTIONS
NORMAL FRONT PANEL OPERATION
For "normal operation" (front panel operation): Jumper between 15 and 16, 17 and 18, 40 and 50,
42 and 52, 44 and 54, 48 and 49; as shown in Figure 4-1:
The MOD Power Supplies, as shipped from the factory, аге wired for "normal" power supply орега-
tion. The metal strap on the front panel binding posts should be connected between the chassis ground
and the low side of the power supply to reduce the output noise. In the "normal" power supply орега!-
ing mode, the sense leads are connected to the Коп! panel binding posts. The unit, when in operation,
will function as a constant voliage power supply at the voltage set by the front panel voltage control
knobs. As the output or load current is increased, the unit will automatically crossover to а constant
current mode of operation. The point of crossover from constant voltage to constant current is set by
the current control knobs on the front panel. To obtain the best regulation in the constant current mode
of operation, the meter switch should be in the "current" position. (Note: The meter can draw up to
100 microamps from the power supply output current if the meter switch is in the VOLTAGE position.
This will reduce the degree of current regulation by 100 microamps.)
To set the constant current point, set the meter switch to "current," short the output terminals of the
supply together and adjust the current control knobs for the required current as indicated by the meter.
бо) s1 G2) 53 Gs) ss 56. 57. 38.59
FIGURE 4-1
EXTERNAL VOLTAGE SENSE
For external voltage sense: Jumper between 17 and 18, 40 and 50, 42 and 52, 44 and 54; 16 is (+) sense
_ lead, 49 is (-); see Figure 4-2.
The sense leads must be connected to the correct polarity at the load. The sense leads will draw !ess than
2 milliamps, but a finite voltage drop will occur in the sense leads due to the sense current. Adequate рге-
cautions
should
be
taken
with
regard
to
the
sense
lead
length
and
wire
size
based
on
2
milliamps
of
sense
current
and
the
degree
of
voltage
regulation
required
at
the
load.
The
voltage
drop
between
the
output
of the power supply and the load should not exceed 1 volt.
In
order
to
minimize
noise
pickup
in
the
sense
leads,
they
should
either
be
twisted
together
or
shielded.
The
low
side
of
the
power
supply
should
be
connected
to
chassis
ground
either
at
the
front
panel
or
the
rear
panel.
If
rear
panel
connection
is
desired,
connect
a
jumper
between
Pin
20
(20
through
29)
and
the
low
output
side
of
the
power
supply,
Pin
00
(00
through
09)
for
(+)
voltage,
or
Pin
30
(30
through
39) for (-) voltage.