User Manual
ADCP-75-114 • Issue 2C • January 2002
Page 21
©
2002,
ADC
Telecommunications,
Inc.
Table 5. Fault Isolation and Troubleshooting
Alarm Type Minor
ALARM Indicator: Yellow
Problem The RIU is overheating.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1.
Air
intake
or
exhaust
openings
to
RIU
chassis
blocked.
2.
Ambient
temperature
>
58º
C/136º
F.
3.
Faulty
fan.
4.
Faulty
RIU.
1.
Remove
cause
of
air-flow
blockage.
2.
Reduce
ambient
temperature.
3.
Replace
fan
(see
Section
4.3).
4.
Replace
RIU.
Alarm Type: Major
ALARM Indicator Red:
Problem Over or undercurrent condition detected at power amplifier.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1.
Faulty
RIU.
1.
Replace
RIU.
Alarm Type Major
ALARM Indicator Off
Problem The RIU is not powered.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1.
AC
power
source
off
or
disconnected.
2.
Faulty
RIU
1.
Restore
AC
power.
2.
Replace
RIU.
4.3 Fan Replacement
It
is
recommended
that
the
fan
(catalog
number
DGVI-200000FAN)
be
replaced
every
five
years.
Replacement
of
a
fan
requires
that
the
RIU
be
turned
off
for
a
short
period
of
time.
This
will
drop
all
existing
calls,
cause
a
temporary
loss
of
service,
and
generate
a
major
alarm.
Use
the
following
procedure
to
replace
the
RIU
cooling
fan:
1.
Before
touching
the
RIU
or
handling
a
fan,
slip
on
an
Electro-Static
Discharge
(ESD)
wrist
strap
and
connect
the
ground
wire
to
an
earth
ground
source.
Wear
the
ESD
wrist
strap
while
completing
each
section
of
the
fan
installation
procedure.
Warning:
Electronic
components
can
be
damaged
by
static
electrical
discharge.
To
prevent
ESD
damage,
always
wear
an
ESD
wrist
strap
when
working
on
the
RIU
and
when
handling
electronic
components.
2.
Notify
the
NOC
or
alarm
monitoring
system
operator
that
the
system
is
going
offline.
3.
Place
the
RIU
AC
power
On/Off
switch
in
the
OFF
position
(press
O)
and
disconnect
the
AC
power
cord.
Caution:
High
voltage
components
are
present
within
the
RIU
enclosure.
Disconnect
the
AC
power
cord
from
the
AC
power
source
before
proceeding
to
step
4.
4.
Remove
the
four
flat-head
screws
(requires
TORX
screwdriver
with
T15
bit)
that
secure
the
fan/grill
assembly
to
the
side
of
the
enclosure
as
shown
in
Figure
15
and
save
for
reuse.