Instruction Manual
12
PDC24
/
PAC
October
200
5
–
Iss
ue 3
Triguard
SC300E
Front
panel
LEDs
Check
that
the
green
LED
(Normal)
is
on
and
the
red
LED
(Fault)
is
off.
A fault
condition
can
be
due
to:
• A failure
of
the
ac/dc
input
supply
• An
output
below
5.1V
• An
SMPS
over
temperature
condition.
Check
that
the
yellow
LED
(Power
Share)
is
on.
It
extinguishes
when
the
other
PSU
is
supplying
the
greater
current.
If
the
Power
Share
LED
is
extinguished
and
no
fault
is
indicated
on
either
PSU,
there
could
be an
imbalance
in
output
between
the
two
PSUs.
CALIBRATION
Calibration
is
not
required
in
normal
operation.
Calibration
of
PSUs
must
not
be
performed
on
a running
system.
Use
the
front
panel
trimmers
to
adjust
the
balance
until
both
Power
Share
LEDs
are
illuminated.
The
voltage
between
pins
6 and
7 of
both
test
sockets
will
be
the
same
if
the
PSUs
are
power
sharing
to
any
extent.
If
this
voltage
is
being
measured
while
adjusting
a
trimmer,
the
other
PSU
will
need
to
be
switched
off
(or
short
circuit
pins
1 and
5 of
one
test
socket
to
disable
current
sharing)
to
see
any
effect
on
the
meter.
Adjust
both
PSUs
until
the
voltage
is
the
same
(normally
5.4V
± 0.01V).