IBM EXP400 Type 1733 User manual

IBM EXP400 Storage Expansion Unit
Type 1733
Hardware Maintenance Manual and Troubleshooting
Guide
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IBM EXP400 Storage Expansion Unit
Type 1733
Hardware Maintenance Manual and Troubleshooting
Guide
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Note
Before using this information and the product it supports, be sure to read Appendix C, “Notices,” on
page 79.
Eighth Edition (April 2004)
© Copyright International Business Machines Corporation 2002. All rights reserved.
US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract
with IBM Corp.

About this manual
This manual contains diagnostic information, a Symptom-to-FRU index, service
information, and configuration information for the IBM
®
EXP400 Storage Expansion
Unit.
Important safety information
Be sure to read all caution and danger statements in this book before performing
any of the instructions. See “Safety information” on page 37.
Lea todas as instruções de cuidado e perigo antes de executar qualquer operação.
Prenez connaissance de toutes les consignes de type Attention et Danger avant de
procéder aux opérations décrites par les instructions.
Lesen Sie alle Sicherheitshinweise, bevor Sie eine Anweisung ausführen.
© Copyright IBM Corp. 2002 iii

Accertarsi di leggere tutti gli avvisi di attenzione e di pericolo prima di effettuare
qualsiasi operazione.
Lea atentamente todas las declaraciones de precaución y peligro ante de llevar a
cabo cualquier operación.
Online support
You can download the most current diagnostic, H8 flash, and device driver files
from http://www.ibm.com/pc/support on the World Wide Web.
Support telephone numbers
View support telephone numbers at http://www.ibm.com/planetwide/ on the World
Wide Web.
iv IBM EXP400 Storage Expansion Unit Type 1733: Hardware Maintenance Manual and Troubleshooting Guide

Contents
About this manual . . . . . . . . . . . . . . . . . . . . . . . iii
Important safety information . . . . . . . . . . . . . . . . . . . . iii
Online support . . . . . . . . . . . . . . . . . . . . . . . . .iv
Support telephone numbers . . . . . . . . . . . . . . . . . . . .iv
Chapter 1. General information . . . . . . . . . . . . . . . . . . .1
Related publications . . . . . . . . . . . . . . . . . . . . . . .1
Notices and statements used in this publication . . . . . . . . . . . . .2
Features and operating specifications . . . . . . . . . . . . . . . . .2
Major components of the expansion unit . . . . . . . . . . . . . . . .4
What your expansion unit offers . . . . . . . . . . . . . . . . . . .4
Expansion unit bays . . . . . . . . . . . . . . . . . . . . . . .6
Hot-swap hard disk drive bays . . . . . . . . . . . . . . . . . . .6
Bridge card bay . . . . . . . . . . . . . . . . . . . . . . . .6
Hot-swap ESM and power supply bays . . . . . . . . . . . . . . .7
Expansion unit controls, LEDs, components, connectors . . . . . . . . . .7
Front view . . . . . . . . . . . . . . . . . . . . . . . . . .7
Rear view: ac power supply with fan units . . . . . . . . . . . . . .9
Rear view: ESMs . . . . . . . . . . . . . . . . . . . . . . .10
Power features . . . . . . . . . . . . . . . . . . . . . . . . .11
Turning on the expansion unit . . . . . . . . . . . . . . . . . .11
Turning off the expansion unit . . . . . . . . . . . . . . . . . .11
Turning off the expansion unit in an emergency . . . . . . . . . . . .12
Turning on the expansion unit after an emergency . . . . . . . . . . .12
System-management software support . . . . . . . . . . . . . . . .13
Chapter 2. ESM configuration switches . . . . . . . . . . . . . . .15
Chapter 3. Information for the -48 volt dc power model . . . . . . . . .19
Connecting the power supply to a power-distribution unit . . . . . . . . .20
Disconnecting and removing the dc power supply . . . . . . . . . . . .21
Installing the dc power supply . . . . . . . . . . . . . . . . . . .22
Chapter 4. Installing and replacing components . . . . . . . . . . .23
Installation guidelines . . . . . . . . . . . . . . . . . . . . . .23
System reliability guidelines . . . . . . . . . . . . . . . . . . .23
Handling static-sensitive devices . . . . . . . . . . . . . . . . .23
Working with hot-swap hard disk drives . . . . . . . . . . . . . . . .24
Replacing a hot-swap hard disk drive . . . . . . . . . . . . . . . .25
Replacing a bridge card . . . . . . . . . . . . . . . . . . . . .26
Replacing an ESM . . . . . . . . . . . . . . . . . . . . . . .27
Replacing a hot-swap power supply with fan unit . . . . . . . . . . . .28
Chapter 5. Symptom-to-FRU index . . . . . . . . . . . . . . . . .31
Chapter 6. Parts listing . . . . . . . . . . . . . . . . . . . . .33
Appendix A. Getting help and technical assistance . . . . . . . . . .35
Before you call . . . . . . . . . . . . . . . . . . . . . . . . .35
Using the documentation . . . . . . . . . . . . . . . . . . . . .35
Getting help and information from the World Wide Web . . . . . . . . . .35
Software service and support . . . . . . . . . . . . . . . . . . .36
Hardware service and support . . . . . . . . . . . . . . . . . . .36
© Copyright IBM Corp. 2002 v

Appendix B. Related service information . . . . . . . . . . . . . .37
Safety information . . . . . . . . . . . . . . . . . . . . . . . .37
General safety . . . . . . . . . . . . . . . . . . . . . . . .37
Electrical safety . . . . . . . . . . . . . . . . . . . . . . . .38
Safety inspection guide . . . . . . . . . . . . . . . . . . . . .39
Handling electrostatic discharge-sensitive devices . . . . . . . . . . .40
Grounding requirements . . . . . . . . . . . . . . . . . . . .41
Safety notices (multi-lingual translations) . . . . . . . . . . . . . .41
Appendix C. Notices . . . . . . . . . . . . . . . . . . . . . .79
Edition notice . . . . . . . . . . . . . . . . . . . . . . . . .79
Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . .80
Important notes . . . . . . . . . . . . . . . . . . . . . . . . .80
Product recycling and disposal . . . . . . . . . . . . . . . . . . .81
Electronic emission notices . . . . . . . . . . . . . . . . . . . .81
Federal Communications Commission (FCC) statement . . . . . . . . .81
Industry Canada Class A emission compliance statement . . . . . . . .81
Australia and New Zealand Class A statement . . . . . . . . . . . .82
United Kingdom telecommunications safety requirement . . . . . . . . .82
European Union EMC Directive conformance statement . . . . . . . . .82
Taiwanese Class A warning statement . . . . . . . . . . . . . . .82
Chinese Class A warning statement . . . . . . . . . . . . . . . .82
Japanese Voluntary Control Council for Interference (VCCI) statement . . .83
Power cords . . . . . . . . . . . . . . . . . . . . . . . . . .83
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
vi IBM EXP400 Storage Expansion Unit Type 1733: Hardware Maintenance Manual and Troubleshooting Guide

Chapter 1. General information
The IBM EXP400 Storage Expansion Unit, referred to in this manual as expansion
unit, provides high-capacity, small computer system interface (SCSI) disk storage. It
supports up to seven Ultra320 SCSI hard disk drives on each half of the dual bus. It
delivers fast, high-volume data transfer, retrieval, and storage functions across
multiple drives, to multiple hosts. The expansion unit is designed for continuous,
reliable service; the modular, redundant disk drives, power supply with fan units,
and SCSI Bus Expander and Enclosure Services Module (referred to in this book as
ESM) use hot-swap technology for easy replacement without turning off the
expansion unit. For more information, see “What your expansion unit offers” on
page 4.
Expansion unit models 1RU and 1RX come with two 500-watt ac power supply with
fan units, one ESM (the second ESM is optional), a filler panel to cover the empty
ESM bay, and 14 drive filler panels. Expansion unit model 2RX comes with two -48
volt dc power supply with fan units, two ESMs, and 14 drive filler panels. The drive
filler panels are replaced with hard disk drive options.
Related publications
This Hardware Maintenance Manual and Troubleshooting Guide is in Portable
Document Format (PDF) on the IBM Support Web site,
http://www.ibm.com/pc/support/. It contains information to help you solve problems
yourself, and it contains information for service technicians.
v Installation Guide
This printed publication contains instructions for setting up your expansion unit
and basic instructions for installing some options.
v User’s Guide
This publication provides general information about your expansion unit, including
information about features and how to configure and use your expansion unit.
v Safety Information
This publication is in PDF on the IBM Documentation CD. It contains translated
caution and danger statements. Each caution and danger statement that appears
in the documentation has a number that you can use to locate the corresponding
statement in your language in the Safety Information book.
v Rack Installation Instructions
This printed publication contains instructions for installing your expansion unit in
a rack.
© Copyright IBM Corp. 2002 1

v Rack-to-Tower Conversion Kit Installation Instructions
This printed publication comes with the Rack-to-Tower Conversion kit and
contains detailed instructions for converting a rack-model expansion unit to a
tower-model expansion unit.
Your
expansion unit documentation might be updated occasionally to include
information about new features, a translated version of the documentation might be
available in your language, or technical updates might be available to provide
additional information that is not included in your expansion unit documentation.
These updates are available from the IBM Web site. Complete the following steps
to check for updated documentation and technical updates:
1. Go to http://www.ibm.com/pc/support/.
2. In the Learn section, click Online publications.
3. On the “Online publications” page, in the Brand field, select Servers.
4. In the Family field, select Rack/Storage Enclosures.
5. Click Display documents.
Notices and statements used in this publication
The caution and danger statements that appear in this publication are also in the
multilingual Safety Information publication, which is on the IBM Documentation CD.
Each statement is numbered for reference to the corresponding statement in the
Safety Information publication.
The following notices and statements are used in this publication:
v Notes: These notices provide important tips, guidance, or advice.
v Important: These notices provide information or advice that might help you avoid
inconvenient or problem situations.
v Attention: These notices indicate potential damage to programs, devices, or
data. An attention notice is placed just before the instruction or situation in which
damage could occur.
v Caution: These statements indicate situations that can be potentially hazardous
to you. A caution statement is placed just before the description of a potentially
hazardous procedure step or situation.
v Danger: These statements indicate situations that can be potentially lethal or
extremely hazardous to you. A danger statement is placed just before the
description of a potentially lethal or extremely hazardous procedure step or
situation.
Features and operating specifications
Table 1 on page 3 contains a summary of the features and operating specifications
for your expansion unit. Depending on your expansion unit model, some features
might not be available, or some specifications might not apply.
2 IBM EXP400 Storage Expansion Unit Type 1733: Hardware Maintenance Manual and Troubleshooting Guide

Table 1. Features and operating specifications
General:
v Modular components
– High-capacity disk drives
– SCSI Bus Expander and
Enclosure Services Module
(ESM)
– Power supplies with built-in fan
units
v
Technology
– Supports disk array technology
– Supports clustering
– SCSI (Ultra320) host interface,
redundant data storage, power
and cooling system, and ESMs
– Hot-swap technology for hard
disk drives, power supply with
fan units, and ESMs
v
User interface
– Built-in power, activity, and fault
indicators, identification labeling
on CRUs, rear indicator lights,
switches, and connectors
– Easy-to-replace drives, power
supplies with built-in fan units,
and ESMs
Hard
disk drive storage:
v Current capabilities:
– Maximum hard disk drives per
expansion unit: 14
– Hard disk drives per SCSI bus
segment: 7
– SCSI buses per unit: 2
– SCSI buses can be configured
as one continuous SCSI bus.
ESMs:
v Technology and interfaces:
– SCSI: Ultra320
– SCSI bus interface: Two 68-pin,
Very High Density Connector
Interface (VHDCI) connectors for
SCSI bus cables
Acoustical noise emissions:
For open bay (no drives installed)
and maximum system configurations
(14 hard disk drives installed).
v Sound power (idling):
– 5.5 bels (open bay)
– 5.7 bels (typical)
v
Sound power (operating):
– 6.0 bels (open bay)
– 6.5 bels (typical)
v
Sound pressure (idling):
– 44 dBA (open bay)
– 47 dBA (typical)
v
Sound pressure (operating):
– 44 dBA (open bay)
– 54 dBA (typical)
AC
power supply with built-in fan:
v Expansion unit model 1RU or 1RX
comes with two hot-swap 500 watt
(115 - 230 V ac) power supply
with fan units.
v The two power supplies provide
redundant power to the expansion
unit.
-48
volt dc power supply:
At a nominal voltage of -48 volt dc,
the expansion unit draws
approximately 5 amperes.
Size:
v Height: 12.8 cm (5.0 in.)
v Depth: 54.0 cm (21.8 in.)
v Width: 44.7 cm (17.6 in.)
v Weight: approximately 24.3 kg
(53.6 lb) for a standard unit. When
fully configured 37.3 kg (82 lb)
Environment:
v Air temperature:
– Expansion unit on: 10° to 40°C
(50.0° to 104°F); altitude: 30.5
(100 ft) below to 3000 m (9840
ft) above sea level;
temperature change: 10°C to
(18°F) per hour
– Expansion unit off: 10° to 50°C
(14.0° to 120.0°F); maximum
altitude: 3000 m (9840 ft);
temperature change: 15°C
(27.0°F) per hour
Environment cont.
v Humidity:
– Expansion unit on: 20% to 80%
– Expansion unit off: 10% to 90%
– Maximum dew point: 26°C (79°F)
– Maximum humidity gradient: 10%
per hour
Heat
output:
Approximate heat output in British
thermal units (Btu) per hour:
v Minimum configuration: 82.4 Btu
(282 watts)
v Maximum configuration: 91.0 Btu
(311 watts)
Electrical
input:
v Sine-wave input (50-60 Hz) required
v Input voltage low range:
– Minimum: 90 V ac
– Maximum: 136 V ac
v
Input voltage high range:
– Minimum: 198 V ac
– Maximum: 264 V ac
v
Input kilovolt-amperes (kVA),
approximately:
– Minimum: 0.06 kVA
– Maximum: 0.45 kVA
Notes:
1. Power consumption and heat
output vary depending on the
number and type of optional
features installed and the
power-management optional
features in use.
2. These levels were measured in
controlled acoustical environments
according to the procedures
specified by the American National
Standards Institute (ANSI) S12.10
and ISO 7779 and are reported in
accordance with ISO 9296. Actual
sound-pressure levels in a given
location might exceed the average
values stated because of room
reflections and other nearby noise
sources. The declared sound-power
levels indicate an upper limit, below
which a large number of computers
will operate.
Chapter 1. General information 3

Major components of the expansion unit
The orange color on components and labels in the expansion unit indicates
hot-swap or hot-plug components. You can install or remove these components
while the expansion unit is running. For information about installing hot-swap and
hot-plug components, see Chapter 4, “Installing and replacing components,” on
page 23.
The blue color on components and labels indicates touch points, where a
component can be gripped, a latch moved, and so on.
The following illustration shows the locations of major components in your
expansion unit.
Note: The illustrations in this publication might differ slightly from your hardware.
Hot-swap power supply with fan units
Hot-swap ESMs
Hard disk drives Filler panel
What your expansion unit offers
The expansion unit provides several features for easy operation, including:
v Customer replaceable units (CRUs)
The CRUs in your expansion unit are: Ultra320 hard disk drives, ESMs, and
power supply with fan units.
v Fault indicators
All CRUs have fault or status light emitting diodes (LEDs) to indicate hardware
failures.
v Switch selectable Box ID and user configuration settings
The ESM contains five sets of configuration switches that you can set according
to your configuration. For detailed information about these switches and their
settings, see Chapter 2, “ESM configuration switches,” on page 15.
v
Redundant cooling and power capabilities
Expansion unit models 1RU and 1RX use a dual ac input power system. This
means both power switches must be turned on for proper redundant operation.
The redundant cooling of the fans in your expansion unit enables continued
operation if one fan fails. Your expansion unit comes with two 500-watt hot-swap
power supply with fan units, which provide redundant power for many expansion
4 IBM EXP400 Storage Expansion Unit Type 1733: Hardware Maintenance Manual and Troubleshooting Guide

unit configurations. If the average load on your expansion unit is less than 500
watts and a problem occurs with one of the power supplies, the other power
supply can meet the power requirements.
Expansion unit model 2RX uses a dual dc input power system. For detailed
information about working with the dual dc input power system, see Chapter 3,
“Information for the -48 volt dc power model,” on page 19.
v ServeRAID
™
support
Your expansion unit supports servers with ServeRAID adapters to create
redundant array of independent disks (RAID) configurations.
v Clustering support
Twin-tailed clustering support is a feature of the expansion unit. Clustering is a
way to share SCSI buses and hard disk drives between two SCSI controllers to
provide redundancy of SCSI controllers and servers. This redundancy is
important if one of the controlling servers fails. If a hardware component fails
after clustering is set up, another server will take ownership of the hard disk
drives.
With twin-tailed clustering, you can connect two IBM ServeRAID controllers to an
expansion unit. In the twin-tailed clustering environment, you can use dual-host
controllers cabled separately to the expansion unit; however, only a single bus of
13 drives is supported. Each SCSI device on a SCSI bus must have a unique ID.
Service tip: If you use IBM ServeRAID controllers in a cluster configuration, the
termination-power LED on the back of the expansion unit is useful. The
ServeRAID controller provides the signal for termination power. If the termination
power LED is not lit, it indicates that a particular expansion unit is not attached to
a controller that is turned on. Make a note of which expansion unit is attached to
which server before the hardware is serviced.
Clustering requires additional hardware and specialized software. For more
information, go to http://www.ibm.com/pc/ww/eserver/xseries/clustering/.
Chapter 1. General information 5

Expansion unit bays
The following sections describe the hot-swap components of the expansion unit and
the bridge card bay.
With the hot-swap features of the expansion unit, you can remove and replace a
hard disk drive, power supply with fan unit, and ESM without turning off the
expansion unit. You can maintain the availability of your expansion unit while a
hot-swap component is removed, installed, or replaced.
Hot-swap hard disk drive bays
The following illustration shows the location of the hot-swap hard disk drive bays
that are accessible from the front of your expansion unit. The expansion unit
supports up to 14 IBM Ultra320 SCSI hard disk drives. These drives come
preassembled in a drive tray. You install the hard disk drives in the 14 drive bays on
the front of the expansion unit.
In the following illustration, seven of the 14 hard disk drive bays contain hard disk
drives, and seven bays contain filler panels. To maintain proper cooling within your
expansion unit, always keep a filler panel in each drive bay that does not contain a
hard disk drive. For information about installing and replacing drives, see “Working
with hot-swap hard disk drives” on page 24.
Attention: Never hot-swap a hard disk drive when its green activity LED is
flashing. Hot-swap a hard disk drive only when its amber status LED is lit (not
flashing) or when the drive is inactive with the green activity LED off (not flashing).
Use the ServeRAID system-management software to set the hard disk drive state to
“defunct” and then you can hot-swap it.
Bridge card bay
The following illustration shows the location of the bridge card bay. This bay is
accessible from the front of the expansion unit. You can replace the bridge card, but
you must turn off the expansion unit before doing so. For more information about
replacing a bridge card, see “Replacing a bridge card” on page 26.
Bridge card bay
Hot-swap drive bays Filler panel
Bridge card bay
6 IBM EXP400 Storage Expansion Unit Type 1733: Hardware Maintenance Manual and Troubleshooting Guide

Hot-swap ESM and power supply bays
The following illustration shows the location of the hot-swap ESM bays (for the
hot-swap ESMs) and the power supply bays (for the hot-swap power supply with
fan units).
Hot-swap ESM bays
The expansion unit comes with two ESM bays for the hot-swap ESMs.
ESMs provide a SCSI interface to the hard disk drives and monitor the
overall status of the expansion unit. An ESM has five sets of switches for
user configuration. For more information about replacing an ESM, see
“Replacing an ESM” on page 27. For more information about ESM
switches, see Chapter 2, “ESM configuration switches,” on page 15.
Hot-swap power supply with fan unit bays
Expansion unit models 1RU and 1RX come with two 500 watt hot-swap and
redundant power supply with fan units. The power supplies are redundant in
that a single power supply can provide adequate power and cooling for the
entire expansion unit. A single power supply can support up to 14 hard disk
drives; however, both power supplies must be installed, even if one power
supply is not operational. For more information about working with hot-swap
power supplies, see “Replacing a hot-swap power supply with fan unit” on
page 28.
Expansion unit model 2RX comes with two -48 volt dc power supply with
fan units. For information about installing or replacing the -48 volt power
supplies, see Chapter 3, “Information for the -48 volt dc power model,” on
page 19.
Expansion unit controls, LEDs, components, connectors
The primary controls of the expansion unit are located on the front of the unit. The
user controls of the expansion unit are located on the back of the unit. Two
hot-swap power supply with fan units and two ESMs are accessible from the back
of the expansion unit. These components contain several user indicators and
connectors.
Front view
The primary controls on the front of the expansion unit are shown in the following
illustration and are described in this section.
Hot-swap power supply with fan units
Hot-swap ESMs
Chapter 1. General information 7

Power-on LED (green)
This green LED is lit when the power supply is turned on and is supplying
both 5 volt and 12 volt dc power to the expansion unit.
General-system-error LED (amber)
When lit, this amber LED indicates that the unit has a fault, such as in a
power supply, ESM, or hard disk drive.
Box identity (blue)
The box identity LED is used to identify the expansion unit. When this blue
LED is lit, the system-management software on the server connected to the
expansion unit has identified this expansion unit.
Bridge card bay
The bridge card is located in the center of the front panel between bay 7
and bay 8.
Filler panel
Expansion units come with drive filler panels in the unused drive bays.
Before installing new hard disk drives, you must remove the filler panels
and save them for later use. Each of the 14 bays must contain either a filler
panel or a hard disk drive.
Drive bays
There are 14 drive bays that contain either a hard disk drive or a filler
panel.
Latch This multipurpose blue latch releases or locks the hard disk drive in place.
Tray handle
You can use this multipurpose handle to insert or remove a hard disk drive.
Status LED (amber)
Each hard disk drive has a status LED. When lit continuously, this amber
LED indicates a drive failure. When flashing, this amber LED indicates that
a drive Identify or Rebuild is in progress.
Activity LED (green)
Each hard disk drive has an activity LED. When flashing, this green LED
indicates drive activity.
Hard disk drive
You can install up to 14 hot-swap hard disk drives in the expansion unit.
Each drive contains an Ultra320 hard disk drive and tray.
Power-on LED (green)
activity
LED (green)
Hard disk
drive
General-system-
error LED (amber)
status
LED (amber)
Hard disk
drive
Drive bays
Tray
handle Latch
Bridge
card bay
Hard disk
drive
Filler panel
Box identity LED
(blue)
8 IBM EXP400 Storage Expansion Unit Type 1733: Hardware Maintenance Manual and Troubleshooting Guide

Rear view: ac power supply with fan units
Two hot-swap power supply with fan units are accessible from the back of the
expansion unit. These components at the back of the expansion unit contain
several user controls, LEDs, and connectors as shown in the following illustration.
Thumbscrews
Loosen the thumbscrews to remove or install a power supply with fan unit.
AC power connector
The power cord for the power supply with fan unit connects here.
Power supply with fan unit
The two hot-swap power supply with fan units are located on the back of
the expansion unit.
Attention: The expansion unit comes with two power supply with fan
units installed. When one power supply fails, the power-supply unit must be
replaced to reestablish redundancy. When replacing the failed unit with the
new power supply unit, ensure that this operation is performed in less than
10 minutes to prevent overheating.
The fan that is visible from the rear of the power supply is an auxiliary fan
that is normally off. This fan turns on only when the main fan within the
power supply fails.
Power on/off switch
Use this switch to turn the power supply on and off.
Fault LED (amber)
When lit continuously, this amber fault LED indicates a power supply failure
or that a redundant power supply is not turned on. This LED also flashes
when the built-in fan fails.
DC power LED (green)
This green LED is lit when the expansion unit is turned on and is supplying
both 5 volt and 12 volt dc power to the expansion unit.
AC power LED (green)
This green LED is lit when the power supply is receiving ac power.
Handles
The two handles are used for installing and removing the power supply with
fan unit.
Thumbscrews Thumbscrews
AC power connectorAC power connector
Power
supply/Fan CRU
Power
supply/Fan CRU
AC power LED (green)
DC power LED (green)
Fault LED (amber)
Power
on/off
switch
Power
on/off
switch
Handle Handle
Chapter 1. General information 9

Rear view: ESMs
The ESMs are accessible from the back of the expansion unit. These components
contains user controls, LEDs, switches, and connectors as shown in the following
illustration.
Note: The ESM on the right side is optional on expansion unit models 1RU and
1RX.
ESM Each ESM contain SCSI controls, LEDs, and connectors.
Fault LED (amber)
When lit, this amber LED indicates an ESM failure.
SCSI reset LED
When lit, this green LED indicates a SCSI bus reset.
Thumbscrews
Each ESM has a thumbscrew on the left side of the module. Use the
thumbscrew and lever to remove and insert the ESM.
Termination-power LED (green)
When lit, this green LED indicates that termination power is present. When
a termination-power LED is lit, it indicates that the other end of the SCSI
bus connector is connected to a powered-on controller. Each external bus
has a separate termination-power LED.
LVD/SE LED (green)
When lit, this green LED indicates that the external host bus is in low
voltage differential (LVD) mode. When this LED is off, it indicates that the
external host bus is in single-ended (SE) mode. Each external bus has a
separate LVD/SE LED. Only LVD host bus controllers are supported.
SCSI bus connector
The 68-pin Very High Density Connector Interface (VHDCI) connectors are
for connecting your SCSI cables to SCSI bus 1 and SCSI bus 2.
Activity LED (green)
When lit, this green LED indicates there is activity on the external SCSI
bus. Both external buses have a separate activity LED.
Termination-power
LED (green)
Termination-power
LED (green)
LVD/SE
LED (green)
LVD/SE
LED (green)
SCSI Bus
connector 2
SCSI Bus
connector 1
Activity LED
(green)
Activity LED
(green)
ESM
ESM
Thumbscrew
SCSI reset
LED (green)
SCSI reset
LED (green)
Fault LED
(amber)
Fault LED
(amber)
Box ID switch (SW2)
Configuration switch (SW1)
Switch cover
10 IBM EXP400 Storage Expansion Unit Type 1733: Hardware Maintenance Manual and Troubleshooting Guide

Configuration switch SW1
Configuration switch SW1 is a 5-position switch that is mounted on the
ESM and is accessible from the rear of the expansion unit.
Box ID switch SW2
Box ID switch SW2 is a 10-position rotary switch that sets the expansion
unit ID using values 0 through 9. System-management software, such as
IBM Director or ServeRAID Manager, uses this ID when it provides data
and alerts for the expansion unit.
Power features
This section contains instructions for turning the expansion unit on and off under
normal and emergency circumstances.
Turning on the expansion unit
If you are turning on the expansion unit after an emergency shutdown or power
outage, see “Turning on the expansion unit after an emergency” on page 12.
Complete the following steps to turn on the power for the initial startup of the
expansion unit.
1. Verify that:
a. All cables are properly attached.
b. Both power cords are plugged into the back of the expansion unit and into
properly grounded electrical outlets.
c. All hard disk drives are locked securely in place.
d. The configuration switches are set correctly. See Chapter 2, “ESM
configuration switches,” on page 15.
2.
Check the system documentation for all the hardware devices you intend to turn
on and determine the proper power-on sequence.
Note: Be sure to turn on the expansion unit before or at the same time as you
turn on the server.
3. Turn on each device, based on the power-on sequence that is described in the
documentation that comes with the device.
4. Turn on both power supplies on the back of the expansion unit.
The expansion unit might take a few seconds to turn on. During this time, you
might see the fault (amber) and the power (green) LEDs on the expansion unit
turn on and off intermittently. When the power-on sequence is complete, only
the power (green) LEDs on the front and back should remain on. If one or more
fault (amber) LEDs remain lit, refer to Chapter 5, “Symptom-to-FRU index,” on
page 31.
Turning off the expansion unit
Attention: Except in an emergency situation, never turn off the power if any fault
LEDs are lit on the expansion unit. Correct the fault before you attempt to turn off
the power, using the proper troubleshooting or servicing procedure. This will ensure
that the expansion unit will turn on correctly later. See Chapter 5, “Symptom-to-FRU
index,” on page 31.
Statement 5:
Chapter 1. General information 11

CAUTION:
The power control button on the device and the power switch on the power
supply do not turn off the electrical current supplied to the device. The device
also might have more than one power cord. To remove all electrical current
from the device, ensure that all power cords are disconnected from the power
source.
1
2
The expansion unit is designed to run continuously, 24 hours a day. Turn off the
power only when at least one of the following is true:
v Instructions in a hardware or software procedure require you to turn off the
power.
v A service technician tells you to turn off the power.
v A power outage or emergency situation occurs. See “Turning off the expansion
unit in an emergency.”
Complete
the following steps to turn off the expansion unit:
1. Close all active operating system windows and programs.
2. Power down the server attached to the expansion unit.
3. Make sure that all amber status and fault LEDs are off. If any status or fault
LEDs are lit (on hard disk drives, power supplies, or ESMs), identify or correct
the problem before you turn off the power. For more information, see Chapter 5,
“Symptom-to-FRU index,” on page 31.
4. Turn off both power supplies.
Turning off the expansion unit in an emergency
Attention: Emergency situations might include fire, flood, extreme weather
conditions, or other hazardous circumstances. If a power outage or emergency
situation occurs, always turn off all power switches on all computing equipment.
This will help safeguard your equipment from potential damage due to electrical
surges when power is restored. If the expansion unit loses power unexpectedly, it
might be due to a hardware failure in the power system or midplane, see Chapter 5,
“Symptom-to-FRU index,” on page 31.
Complete the following steps to turn off the expansion unit during an emergency
situation:
1. Close all active operating system windows and programs.
2. Power down the server attached to the expansion unit.
3. If you have time, stop all activity and check the LEDs (front and back). Make
note of any status or fault LEDs that are lit so that you can correct the problem
when you turn on the power again.
4. Turn off all expansion unit power supplies; then, unplug the power cables from
the expansion unit.
Turning on the expansion unit after an emergency
Complete the following steps to restart the expansion unit if you turned off the
power supplies during an emergency shutdown, or if a power failure or a power
outage occurred:
12 IBM EXP400 Storage Expansion Unit Type 1733: Hardware Maintenance Manual and Troubleshooting Guide