I/o modules, Bladecenter t unit power, controls, and indicators, Starting the bladecenter t unit – IBM BladeCenter T Type 8720 User Manual
Page 29: Bladecenter, Unit, Power, Controls, Indicators, Starting, Modules

Note:
The
service
processor,
management
module,
or
systems-management
function
must
monitor
the
alarm
reset
inputs
to
maintain
the
fault
condition
that
you
set
for
the
unit.
The
alarm
reset
inputs
can
be
voltages
in
excess
of
standard
logic
levels,
so
you
must
electrically
or
optically
isolate
them
from
the
monitoring
logic.
Table
4.
Alarms
connector
pinout
Pin
#
Description
I/O
Pin
#
Description
I/O
1
Minor
alarm
reset
+
I
9
Minor
alarm
normally
closed
O
2
Minor
alarm
reset
-
I
10
Minor
alarm
common
O
3
Major
alarm
reset
+
I
11
Major
alarm
normally
open
O
4
Major
alarm
reset
-
I
12
Major
alarm
normally
closed
O
5
Critical
alarm
normally
open
O
13
Major
alarm
common
O
6
Critical
alarm
normally
closed
O
14
Reserved
O
7
Critical
alarm
common
O
15
Reserved
O
8
Minor
alarm
normally
open
O
The
electrical
specifications
for
the
alarms
connector
are
as
follows:
–
Outputs
-
Voltage
range:
0
V
dc
to
-100
V
dc
(maximum
current
0.3
A
at
100
V
dc)
-
Current
range:
0
A
to
1
A
(maximum
voltage
30
V
dc
at
1
A)
-
Worst-case
VA:
1
A
at
-30
V
dc
(30
VA
maximum)
indefinitely
–
Inputs
-
Voltage
range:
0
V
dc
to
-100
V
dc
(including
transients)
-
Differential
input
voltage:
3
V
dc
to
72
V
dc
–
Reset
input
activation
Pulse
width:
200
ms
(minimum)
to
300
ms
I/O
modules
You
can
install
a
maximum
of
four
I/O
modules
at
the
rear
of
the
system
(a
maximum
of
four
Gbit
Ethernet
switches,
or
a
maximum
of
two
Gbit
Ethernet
switches
and
two
Fibre
Channel
switches).
The
minimum
system
configuration
requires
one
Gbit
Ethernet
switch
or
pass-thru
module.
The
I/O
switch
modules
provide
high-performance
connectivity
between
the
blade
servers.
See
the
documentation
that
comes
with
each
I/O
module
for
a
description
of
the
LEDs
and
connectors
on
the
I/O
module.
BladeCenter
T
unit
power,
controls,
and
indicators
This
section
describes
the
controls
and
light-emitting
diodes
(LEDs)
and
how
to
start
and
shut
down
the
BladeCenter
T
unit.
Starting
the
BladeCenter
T
unit
Complete
the
following
steps
to
start
the
BladeCenter
T
unit:
1.
Read
the
information
in
Chapter
1.
General
information
19