Technical data
9050
Diagnostics
5-9
Power Indication LEDs
This chart shows the LEDs that are
lit
for various power supply conditions. It also indicates which
board
is
the most
likely
faulty component.
A
"I"
in
the Fault Location column indicates the Stack PS board.
A
"2"
in
the Fault Location column indicates the
Main
PS Assembly.
A
"3"
in
the Fault Location column indicates the motherboard, or the rest of the sytem.
An
undervoltage condition may require the unplugging of stack and lIO boards
in
order to deter-
mine whether a short
is
in
the power supply or the load. A minimum power supply load must be
maintained and the fans must be connected.
Any
three
of
the following
will
maintain the power
supply load:
• One
Cpu.
• One lOP.
•
Two 512K
RAM
boards.
• SCM board.
• 09855-66525 load board (used
with
9020/9030/9040).
Power Indication LEDs
Chart
Stack
Power
PS
OT
ON
18
Fault
Fault
LED LED
LED
LED
Location
(normal)
off
off
on on
-
2V
undervoltage on
off
off on
1,3 (short)
-
2V
overvoltage on
off
off on 1,3 (short)
6.7V undervoltage on off off on
1,3 (short)
6.7V overvoltage on off off on
1,3 (short)
3.85V undervoltage on
off off on 1,3 (short)
3.85V overvoltage on
off
off on
1,3 (short)
Stack overtemp off on off on
CPU, Fan, or 1
Main supply overtemp
off
on
off
on Fan,
1,
or
2
19V
undervoltage
off
off
off on
1,2,
or
3
19V
overvoltage off
off
off on
1,2,
or
3
-
12V
undervoltage
off
off
off on
1,2,or3
5V
undervoltage
off
off
off
on
2
Overcurrent
off
off off on
1,2,
or 3
+ 12V undervoltage
off
off
off on
1,2,
or
3
Line
fuse
open off
off off
off
2
IB
fuse
open
off
off
off off 2
Cable disconnected
off
off off off
1,2
Voltage Selector at nov
Selector Switch
(220Vinput)
off
off
off off
Fuse
Voltage Selector at
220V
Selector Switch
(110V input)
off
off off on