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Cheetah 4LP Installation Guide, Rev. B
1
Preface
This manual contains information for users of the Seagate®
Cheetah 4LP SCSI disc drives. It provides support services, per-
formance specifications, and initial setup information. Additional
information is available in the Cheetah 4LP Product Manual (part
number 83329120). Contact your Seagate sales representative
if you need to order this publication.
Attention. This high performance Cheetah disc drive MUST
have proper power and cooling considerations for
reliable operation.
Why is there a difference between 10,000 RPM and 7,200 RPM
disc drives?
• Cheetah disc drives spinning at 10,000 RPM will dissipate
more heat than 7,200 RPM class disc drives (typical power
dissipation is 22.5 watts).
• The increased heat is primarily due to increased motor power
dissipated inside the drive.
• The increase in heat dissipation requires that the Cheetah
10,000 RPM disc drives receive more cooling consideration
than 7,200 RPM class disc drives.
• Proper consideration of enhanced cooling by conduction (heat
transfer thru material) can reduce the convection cooling (heat
transfer by air motion) requirements.
Note. Please contact Seagate technical support services or
your distributor’s technical support if you have questions.
2
Cheetah 4LP Installation Guide, Rev. B
Electrostatic discharge protection
Caution. Removal of circuit boards by personnel not perform-
ing depot repair will damage components and may
void the warranty.
All drive electronic assemblies are sensitive to static electricity,
due to the electrostatically sensitive devices used within the
drive circuitry. Although some devices such as metal-oxide
semiconductors are extremely sensitive, all semiconductors, as
well as some resistors and capacitors, may be damaged or
degraded by exposure to static electricity.
Electrostatic damage to electronic devices may be caused by
the direct discharge of a charged conductor or by exposure to
the static fields surrounding charged objects. To avoid damaging
drive electronic assemblies, observe the following precautions
when installing or servicing the drive:
• Ground yourself to the drive whenever the drive electronics
are or will be exposed. Connect yourself to ground with a wrist
strap (Seagate part number 12263496). Connection may be
made to any grounded metal assembly. As a general rule,
remember that you and the drive electronics must all be
grounded to avoid potentially damaging static discharges.
• Turn off the power before removing or installing the DC power
cable.
• Do not remove any circuit boards from the drive.
• Never use an ohmmeter on any circuit boards.
• When installing the drive on a carrier or tray, discharge the
carrier or tray prior to inserting it into the system.
Cheetah 4LP Installation Guide, Rev. B
3
Important safety information and precautions
Caution. Use forced-air ventilation when bench-testing the
drive to ensure proper cooling of drive components.
Use proper safety techniques for safe, reliable operation of this
unit.
The procedures in this manual and labels on the unit contain
warnings and cautions that must be carefully read and followed
to minimize or eliminate the risk of personal injury. The warnings
point out conditions or practices that may endanger you or oth-
ers. The cautions point out conditions or practices that may dam-
age the unit, possibly making it unsafe for use.
Always observe the following warnings and precautions:
• Follow all cautions and warnings in the procedures.
• Use sound safety practices when operating, installing, or
removing the unit.
• Use caution when troubleshooting a unit that has voltages
present. Turn off power to the unit before removing it.
• Ensure that the internal temperature of the rack or cabinet
does not exceed the limits defined for the drive when the drive
is mounted in an equipment rack or cabinet. When units are
stacked vertically, pay special attention to the top where tem-
peratures are usually highest.
• Follow the precautions listed above in “Electrostatic discharge
protection.”
• Do not remove any circuit boards from the drive. Return the
entire drive for depot repair if any circuit board is defective.
Removal of circuit boards by personnel not performing depot
repair will damage components and may void the warranty.
4
Cheetah 4LP Installation Guide, Rev. B
• Do not separate the head and disc assembly (HDA) from the
PCB. Return the entire drive for depot repair if the HDA is
defective.
• Do not attempt to disassemble the HDA. It is not field repair-
able. If the sealed HDA is opened by personnel not performing
depot repair, this will damage components and void the
warranty.
As a component, this drive is designed to be installed and oper-
ated in accordance with UL1950, EN60950, CSA C22.2 950-
M89, and VDE0805.
Seagate takes all reasonable steps to ensure that its products
are certifiable to currently accepted standards. Typical applica-
tions of these disc drives include customer packaging and sub-
system design. Safety agencies conditionally certify component
assemblies, such as the Cheetah disc drive, based on their final
acceptability in the end-use product. The subsystem designers
are responsible for meeting these conditions of acceptability in
obtaining safety-regulatory agency compliance in their end-use
products and for certifying where required by law. A necessary
part of meeting safety requirements is the provision for overcur-
rent protection on drive SELV supply voltages.
This unit is a component part and as such is not meant to comply
with FCC or similar national requirements as a stand-alone unit.
Engineering radiated emissions test results are available
through the Seagate Safety Department to assist the subsystem
designer.
Cheetah 4LP Installation Guide, Rev. B
5
Wichtige Sicherheitshinweise
Vorsicht. Beim Testen des Laufwerks auf dem Prüftisch ist
Fremdbelüftung vorzusehen, um eine ausreichende Kühlung der
Laufwerkkomponenten sicherzustellen.
Verwenden Sie geeignete Sicherheits- um den sicheren, zuver-
lässigen Betrieb dieser Einheit zu gewährleisten.
Die Verfahren in diesem Handbuch und die Aufkleber auf dem
Gerät enthalten Warn- und Vorsichtshinweise. Diese Hinweise
sind sorgfältig durchzulesen und zu beachten, um das Risiko
von Verletzungen auf ein Mindestmaß zu beschränken oder
ganz zu vermeiden. Die Warnhinweise machen auf Situationen
oder Praktiken aufmerksam, die Sie oder andere gefährden
könnten. Die Vorsichtshinweise machen auf Situationen oder
Praktiken aufmerksam, die Einheit beschädigen können, so daß
deren Gebrauch mit Risiko behaftet ist.
Die Warn- und Vorsichtshinweise sind nicht allumfassend! Es ist
uns einfach nicht möglich, alle Wartungsmethoden oder die
eventuellen Risiken jeder Methode zu kennen, zu beurteilen und
Sie entsprechend zu beraten. Aus diesem Grund haben wir auf
eine derartige umfassende Beurteilung verzichtet. Falls Sie ein
hier nicht beschriebenes Verfahren oder Werkzeug verwenden,
stellen Sie zuerst sicher, daß das gewählte Verfahren weder Ihre
persönliche Sicherheit noch die Leistung der Einheit gefährdet.
Beachten Sie in jedem Fall die folgenden Warn-und Vorsicht-
shinweise:
• Beachten Sie alle Warn- und Vorsichtshinweise in diesem
Handbuch.
6
Cheetah 4LP Installation Guide, Rev. B
• Treffen Sie beim Betrieb, bei der Installation oder bei der
Entfernung der Einheit angemessene Sicherheitsvorkehrun-
gen.
• Wenn eine Einheit unter Spannung steht, gehen Sie bei der
Fehlerdiagnose besonders vorsichtig vor. Schalten Sie die
Einheit aus, bevor Sie mit den Installations-und Entfernung-
sarbeiten beginnen.
• Wenn das Laufwerk in einem Einbaugestell oder Gehäuse
montiert ist, sorgen Sie dafür, daß die Temperatur im Inneren
des Gestells oder Gehäuses die für das Laufwerk vorgege-
benen Grenzwerte nicht übersteigt. Wenn Einheiten vertikal
übereinander betestigt werden, achten Sie besonders auf den
oberen Stapelbereich, da dort die Temperatur gewöhnlich am
höchsten ist.
• Befolgen Sie die oben unter “Electrostatic Discharge Protec-
tion” angegebenen Sicherheitsmaßnahmen.
• Nehmen Sie keine Platinen aus dem Laufwerk. Wenn eine
Platine defekt ist, muß das gesamte Laufwerk zur Reparatur
eingeschickt werden. Die Herausnahme von Platinen durch
andere Personen als die für die werkseitige Reparatur zustän-
digen kann zu einer Beschädigung der Komponenten und
Erlöschen des Garantieanspruchs führen.
• Die vormontierte Kopf- und Festplatteneinheit (HDA) nicht aus
dem Laufwerkgehäuse nehmen! Falls die HDA beschädigt ist,
schicken Sie das gesamte Laufwerk zur Reparatur ein.
• Die HDA ist nicht vor Ort reparierbar und darf nicht auseinan-
dergenommen werden! Öffnen der versiegelten HDA durch
andere Personen als die für die werkseitige Reparatur zustän-
Cheetah 4LP Installation Guide, Rev. B
7
digen hat eine Beschädigung der Komponenten und
Erlöschen des Garantieanspruchs zur Folge.
Als Teilkomponente ist dieses Laufwerk für die Installation und
den Betrieb in Übereinstimmung mit UL 1950, EN60950, CSA
C22.2 950-M89 und VDE0805 vorgesehen.
Seagate ist ständig bemüht, die Zulassungsfähigkeit von
Seagate-Produkten im Rahmen der gegenwärtig geltenden
Standards zu gewährleisten. Zu den typischen Anwendungen
dieser Festplattenwerke zählen Systemeinbau durch den
Kunden und die Konstruktion von Untersystemen. Sicherheits-
behörden gewähren eine bedingte Zulassung für Komponenten
wie das Cheetah-Festplattenlaufwerk vorbehaltlich der endgülti-
gen Zulasssung im Endprodukt. Designer von Untersystemen
sind dafür verantwortlich, die Voraussetzungen für die Einhal-
tung sicherheits- oder aufsichtsbehördlicher Vorschriften in ihren
Endprodukten und - falls gesetzlich vorgeschrieben - für die
Zulassung zu schaffen. Eine Grundvoraussetzung zur Einhal-
tung der Sicherheitsanforderungen ist die Bereitstellung eines
Überlastschutzes für die SELV-Versorgungsspannungen des
Laufwerks.
Dieses Gerät ist eine Baugruppe und unterliegt als solche nicht
den Anforderungen der FCC oder ähnlicher nationaler Behörden
für eigenständige Geräte. Technische Testergebnisse zu elek-
tromagnetische Strahlung sind für Designer von Untersystemen
auf Anfrage von der Seagate-Sicherheitsabteilung erhältlich.
8
Cheetah 4LP Installation Guide, Rev. B
Regulatory agency compliance
Electromagnetic susceptibility
As a component assembly, the drive is not required to meet any
susceptibility performance requirements. It is the responsibility of
those integrating the drive within their systems to perform those
tests required and design their system to ensure that equipment
operating in the same system as the drive or external to the sys-
tem does not adversely affect the performance of the drive. See
Table 2, DC power requirements.
Electromagnetic compliance
Seagate uses an independent laboratory to confirm compliance
to the directives/standard(s) for CE Marking and C-Tick Marking.
The drive was tested in a representative system for typical appli-
cations. The selected system represents the most popular char-
acteristics for test platforms. The system configurations include:
• 486, Pentium, and PowerPC microprocessors
• 3.5-inch floppy disc drive
• Keyboard
• Monitor/display
• Printer
• External modem
• Mouse
Although the test system with this Seagate model complies to
the directives/standard(s), we cannot guarantee that all systems
will comply. The computer manufacturer or system integrator
shall confirm EMC compliance and provide CE Marking and C-
Tick Marking for their product.
Cheetah 4LP Installation Guide, Rev. B
9
Electromagnetic compliance for the European Union
If this model has the CE Marking it complies with the European
Union requirements of the Electromagnetic Compatibility Direc-
tive 89/336/EEC of 03 May 1989 as amended by Directive 92/
31/EEC of 28 April 1992 and Directive 93/68/EEC of 22 July
1993.
Australian C-Tick
If this model has the C-Tick Marking it complies with the Austra-
lia/New Zealand Standard AS/NZS3548 1995 and meets the
Electromagnetic Compatibility (EMC) Framework requirements
of Australia’s Spectrum Management Agency (SMA).
10
Cheetah 4LP Installation Guide, Rev. B
Seagate technical support services
If you need assistance installing your drive, consult your dealer.
Dealers are familiar with their unique system configurations and
can help you with system conflicts and other technical issues. If
®
you need additional assistance with your Seagate drive or
other Seagate products, use one of the Seagate technical sup-
port services listed below.
SeaFONE® 1-800-SEAGATE
Seagate’s 800 number (1-800-732-4283) allows toll-free access
to automated self-help services, providing answers to commonly
asked questions, troubleshooting tips, and specifications for disc
drives and tape drives. This service is available 24 hours daily
and requires a touch-tone phone. International callers can reach
this automated self-help service by dialing 408-456-4496.
Online services
Using a modem, you can obtain troubleshooting tips, free utility
programs, drive specifications and jumper settings for Seagate’s
entire product line. You can also download software for installing
and analyzing your drive.
SeaNET™
You can obtain technical information about Seagate products
over the Internet from Seagate’s World Wide Web home page
(http://www.seagate.com) or Seagate’s ftp server (ftp://
ftp.seagate.com). You can also send E-mail with your questions
to DiscSupport @ Seagate.com or TapeSupport @
Seagate.com.
Cheetah 4LP Installation Guide, Rev. B
11
Seagate CompuServe forum
Online technical support for Seagate products is available on
CompuServe. To access our technical support forum, type go
seagate. This forum provides information similar to that found on
SeaBOARD. In addition, you can type questions or browse
through previous questions and answers on the forum mes-
sages.
SeaBOARD®
SeaBOARD is a computer bulletin board system that contains
information about Seagate disc and tape drive products and is
available 24 hours daily. Set your communications software to
eight data bits, no parity, and one stop bit (8-N-1).
Location
Australia
England
France
Germany
Singapore
Taiwan
Phone number
61-2-9756-2359
44-1628-478011
33 1-48 25 35 95
49-89-140-9331
TBA
886-2-719-6075
662-531-8111
Disc: 405-936-1600; Tape: 405-936-1630
Thailand
USA
12
Cheetah 4LP Installation Guide, Rev. B
FAX services
SeaFAX®
You can use a touch-tone telephone to access Seagate’s auto-
mated FAX system to receive technical support information by
return FAX. This service is available 24 hours daily.
Location
Australia
England
USA
Phone number
61-2-9756-5170
44-1628-894084
1-800-SEAGATE or 408-456-4496
Seagate technical support FAX
You can FAX questions or comments to technical support spe-
cialists 24 hours daily. Responses are sent during business
hours.
Location
Australia
England
France
Phone number
61-2-9725-4052
44-1628-890660
33 1-46 04 42 50
49-89-1430-5100
Germany
Hong Kong 852-2368 7173
Japan
81-3-5462-2979
Korea
82-2-556-7294/4251
65-488-7528
886-2-715-2923
Singapore
Taiwan
USA
Disc: 405-936-1685; Tape: 405-936-1683
Cheetah 4LP Installation Guide, Rev. B
13
Direct-support services
Seagate technical support
For one-on-one help, you can talk to a technical support special-
ist during local business hours. Before calling, note your system
configuration and drive model number (STxxxx).
Location
Australia
England
Phone number
61-2-9725-3366 (9:00 A.M. to 5:00 P.M., M–F)
44-1628-894083 (10:00 A.M. to 1:00 P.M.,
2:00 P.M. to 5:00 P.M., M–F)
France
33 1-41 86 10 86 (9:30 A.M. to 12:30 P.M.,
2:00 P.M. to 5:00 P.M., M–F)
Germany
Disc: 49-89-140-9332; Tape: 49-89-140-9333
(9:30 A.M. to 12:30 P.M., 2:00 P.M. to 4:00 P.M.,
M–F)
Hong Kong 852-2368 9918
Korea
82-2-556-8241
Singapore
65-488-7584 (9:00 A.M. to 12:00 P.M., 2:00 P.M.
to 5:00 P.M., M–F)
Taiwan
USA
886-2-514-2237
Please dial 1-800-SEAGATE or 408-456-4496
for the specific product telephone number.
(8:00 A.M. to 1:15 P.M., 2:30 P.M. to 7:00 P.M.,
Central time, M–F)
SeaTDD™ 405-936-1687
Using a telecommunications device for the deaf (TDD), you can
send questions or comments 24 hours daily and exchange mes-
sages with a technical support specialist between 8:00 A.M. to
1:15 P.M. and 2:30 P.M. to 7:00 P.M. (Central time) Monday
through Friday.
14
Cheetah 4LP Installation Guide, Rev. B
Customer service centers
Seagate direct OEM, Distribution, and Systems Integrator cus-
tomers should contact their Seagate service representative for
warranty information. Other customers should contact their place
of purchase. Seagate offers comprehensive customer support
for all Seagate drives. These services are available worldwide.
Location
Phone number
FAX number
Asia Pacific and Australia 65-485-3595
Europe, Middle East,
65-485-4980
and Africa
Japan
USA
Other Americas (Brazil,
Canada, Mexico)
31-2031-67300
81-3-5462-2904 81-3-5462-2979
1-800-468-3472 405-949-6740
31-2065-34320
405-949-6706
405-949-6738
Manufacturer’s representatives
Brazil
MA Informatica
55-11-810-7794 55-21-253-6467
Canada
Memofix
Adtech
905-660-4936
905-812-8099
1-800-624-9857
905-660-8738
905-812-7807
Mexico
Abicom Seamax
SA DE CV
525-546-6965
525-546-4888
Cheetah 4LP Installation Guide, Rev. B
15
General description
Cheetah 4LP SCSI disc drives are high-speed, random-access
digital-data storage devices.
The drive is a component for installation in an enclosure
designed for the drive. This is often a rack within the system or
an external enclosure designed to house one or more disc drives
or other peripheral units. In either case, the disc drive must
receive adequate cooling (refer to “Providing adequate cooling”)
and it must be sufficiently grounded and shielded from emis-
sions. The Cheetah 4LP Product Manual (part number
83329120) contains guidelines for a properly designed
enclosure.
*Model “N” version with 50-pin SCSI I/O connector
Figure 1. Cheetah 4LP family drive
16
Cheetah 4LP Installation Guide, Rev. B
Drive characteristics
Table 1.
Characteristics of the various drives covered by this manual are
given in the following tables.
Interface type:
SCSI Fast-20 (also called
Ultra SCSI1)
Cylinders (user accessable):
Disk rotation:
6,526
10,033 r/min ±0.5%
2.99 msec
Avg. latency:
Seek time2
Average read (typical)
Average write (typical)
7.7 msec
8.7 msec
Internal transfer rate
(variable with zone)
122 to 177 Mbits/sec
Multi-segmented cache
512 Kbytes
1Also operates per SCSI-1/SCSI-2/SCSI-3 protocols.
2Includes on-board controller overhead.
Cheetah 4LP Installation Guide, Rev. B
17
Table 1a. Additional drive characteristics
Legend for following table listing other drive characteristics:
A = capacity, unformatted, Gbytes
B = capacity, formatted, Gbytes1
C = number of read/write data heads
D = max. synchronous SCSI interface transfer rate, Mbytes/sec
Model
A
B
C
8
8
8
8
8
D
ST34501N
ST34501W
ST34501WC
ST34501WD
ST34501DC
6,008
6,008
6,008
6,008
6,008
4,550
4,550
4,550
4,550
4,550
20
40
40
40
40
1Standard OEM units formatted with 512 bytes per sector. The
drive is divided into six-cylinder-wide regions. Each region has
54 spares when formatted for 512-byte sectors.
18
Cheetah 4LP Installation Guide, Rev. B
DC power requirements (Amps)
Table 2.
ST34501
N, W, WC models WD, DC models
+5V8, 10 +12V8
+5V8
+12V8
Voltage regulation5
± 5%
0.88
0.81
± 5%2
± 5%
± 5%2
Max. start current
Peak DC 3, 6, 9
2.2
0.89
0.72
2.2
Delayed motor start
(max)1, 4
0.08
0.08
Peak operating current
Typical DC 1
0.85
0.9
0.89
0.94
1.98
1.05
1.09
—
0.89
0.94
1.98
Maximum DC 1
Maximum (peak) AC 7 1.0
1 Measured with an average reading DC ammeter. Instanta-
neous +12V current peaks will exceed these values.
2 A –10% tolerance is permissible during initial start of the spin-
dle but must return to ±5% before reaching 10,000 RPM. The
±5% must be maintained after the drive signifies that its
power-up sequence has been completed and that the drive is
able to accept selection by the host initiator.
3 See the +12V current profile in the Cheetah 4LP Product Man-
ual (publication number 83329120).
4 This condition occurs when the Motor Start option is enabled
and the drive has not yet received a Start Motor command.
Cheetah 4LP Installation Guide, Rev. B
19
5 See “Conducted noise immunity” in the Cheetah 4LP Product
Manual. The specified voltage tolerance is inclusive of ripple,
noise, and transient response.
6 At power-up, the motor current regulator limits the +12V cur-
rent to an average value of less than value shown in table,
although instantaneous peaks may exceed this value. These
peaks should measure 5 msec duration or less.
7 Minimum current loading for each supply voltage is not less
than 4% of the maximum operating current shown.
8 Use separate ground returns for +5V and +12V supplies.
9 Where power is provided to multiple drives from a common
supply, carefully consider individual-drive power requirements.
Where multiple units are powered on simultaneously, be sure
the peak starting current is available to each device.
10 No terminator power. See 11.7.3.4 in the Cheetah 4LP Prod-
uct Manual.
Table 3.
Dimensions of the drive
mm
in
Height 1.00
Width 4.00
Depth 5.75
25.4
101.6
146.05
Weight 1.3 lb (0.59 kg)
20
Cheetah 4LP Installation Guide, Rev. B
Initial setup information
The general information beginning on this page applies to all of
the Cheetah 4LP drive models. After reading the general infor-
mation topics, refer to the appropriate drive-specific section
listed below for additional information about configuring and
installing your particular model.
Drive models
Page
ST34501N
39
ST34501W/WD
ST34501WC/DC
43
48
General information
The following general information topics are discussed:
• SCSI ID jumpers
• Drive termination
• Terminator power
• Interface drivers and data path width notes
• Other applicable jumper options
• Providing adequate cooling
• Mounting the drive and connecting cables1
• Formatting the drive
1This mounting procedure does not apply to “WC” or “DC” model
drives. To mount a “WC” or “DC” drive, plug the drive into the
system’s single connector attachment (SCA) position on the
system’s back panel.
Cheetah 4LP Installation Guide, Rev. B
21
SCSI ID jumpers
Each device on the SCSI chain must have a unique SCSI ID.
The host system’s SCSI controller usually uses the ID that has
the highest priority interrupt in the SCSI I/O system. This is
always ID7. ID0 is lowest priority in an 8-bit I/O system. ID8 is
lowest priority in a 16-bit I/O system. The lower priority SCSI IDs
are normally used for other SCSI devices such as this Cheetah
disc drive.
Note. Most SCSI controllers (host adapters) allow you to skip a
SCSI ID. For example, you can have ID0, ID1, and ID3
(skipping ID2). Other controllers do not allow this so be
sure to refer to your system or controller user’s manual
for details about its requirements for proper SCSI device
installation.
Note. This drive is a SCAM (SCSI Configured Auto Magically)
compliant drive. If the system into which you are installing
this drive requires SCAM compliant drives, you do not
need to be concerned about the drive ID jumper settings,
as the system automatically assigns your new drive the
ID it wants it to have. The system may or may not use the
existing drive ID jumper settings. Setting the drive ID
doesn’t hurt anything, but is not necessary in a SCAM
compliant system.
Most Cheetah disc drives are factory set with the SCSI ID set at
0. To change the SCSI ID, refer to the appropriate drive section
for your model.
If, after completing the installation process, the drive’s LED does
not show on/off activity when the host is trying to communicate
with the drive, a duplicate SCSI ID may be the problem. If this is
22
Cheetah 4LP Installation Guide, Rev. B
the case, change the ID so that each device on the SCSI chain
has its own unique ID. Also check your system or controller
user’s manual to ensure that you have not violated its SCSI ID
numbering recommendations.
Drive termination
If you are installing a Cheetah drive in a system that has other
SCSI devices installed, terminate only the end devices on the
SCSI chain. A SCSI “device” is any disc drive, scanner, tape
backup unit, or other piece of hardware connected to your sys-
tem using the SCSI bus.
The top example in Figure 2 shows an internal hard disc at one
end of the SCSI bus with the SCSI controller at the other end
(both are terminated). The bottom example shows two additional
SCSI devices connected externally—this means the SCSI con-
troller is no longer on the end of the SCSI chain and should not
be terminated.
Note. Some controllers prefer to remain terminated even if they
are in the middle of the chain. Also, some controllers treat
the internal and external chains as separate logical
buses. This means you may need to terminate both the
first and last devices on both logical buses to achieve
proper termination. If necessary, refer to your system or
controller documentation to see how this is handled in
your particular system.
For information about how to terminate your drive, refer to the
appropriate drive-specific section.
Cheetah 4LP Installation Guide, Rev. B
23
Internal SCSI cable
Internal
Internal
Controller
SCSI device SCSI device
Terminate
Internal SCSI cable
External
SCSI
cable
Internal
Internal
SCSI device SCSI device
External
External
Controller
SCSI device SCSI device
Terminate
Figure 2. SCSI bus termination
Terminator power
You usually will not need to change this option and can normally
leave the drive configured as it was shipped from the factory. For
information about how to change the terminator power option on
your drive, refer to the appropriate drive-specific section.
I/O circuits and data path widths
• “WD” and “DC” models use differential I/O circuits. You cannot
mix these models with single-ended models (“N,” “W,” “WC”)
on the same SCSI bus. The circuits are incompatible with
each other.
• “W,” “WD,” and “WC” models have a “wide” (16-bit) SCSI data
bus rather than the standard (non-wide) 8-bit SCSI data bus;
however, you can use these wide drives on a standard (non-
wide) 8-bit data bus.
24
Cheetah 4LP Installation Guide, Rev. B
Figures 3a, 3b, 3c, and 3d show typical drive connections. The
following table lists the maximum cable lengths and number of
devices with single-ended I/O circuits allowed on a daisy-chain
cable for 5 and 20 Mbytes/sec I/O data transfer rates.
Table 4.
Cable characteristics for single-ended circuits
I/O transfer
rate
Maximum number of
devices on line
Maximum cable
length allowed
5 Mbytes/s
5 Mbytes/s
20 Mbytes/s
20 Mbytes/s
20 Mbytes/s
8 (reg. SCSI bus)
16 (wide SCSI bus)
4 (reg. SCSI bus)
8 (reg. SCSI bus)
(wide SCSI bus)1
6 meters (19.7 ft.)
6 meters (19.7 ft.)
3 meters (9.8 ft.)
1.5 meters (4.9 ft.)
1
1See system documentation. ANSI spec does not specify a
value here.
For devices having differential I/O circuits, a maximum cable
length of 25 meters (82 feet) is allowed. A maximum of 8 devices
can be connected on an 8-bit wide data bus, and a maximum of
16 devices can be connected on a 16-bit wide data bus.
Cheetah 4LP Installation Guide, Rev. B
25
Figure 3a. 50-pin I/O connection to drive
Figure 3b. 68-pin I/O connection to drive
26
Cheetah 4LP Installation Guide, Rev. B
“N” Model
Drive
2 through X SCSI devices [1]
Pin 1
(check your
adapter for Pin 1 location)
SCSI ID 1
SCSI ID 7
[2]
Host Adapter
PCB
SCSI ID 0
[1] “X” means up to 6 or the maximum allowable number of devices on
the SCSI bus. See system documentation.
Figure 3c. Multiple drive connection to host adapter
Cheetah 4LP Installation Guide, Rev. B
27
“W” Model
Drive
“WD” Model
Drive
Note:
Do not mix
“W” and “WD”
model drives
on the daisy
chain.
[2]
2 through X
SCSI devices [1]
Terminator
Pin 1
SCSI ID 1
(check your
adapter for Pin 1 location)
SCSI ID 7
Host Adapter
PCB
SCSI ID 0
[1] “X” means up to 15 or the maximum allowable number of devices on
the SCSI bus. See system documentation and Table 4.
[2] External terminator. Used only on end “WD” drive.
Figure 3d. Multiple-drive connection to host adapter
28
Cheetah 4LP Installation Guide, Rev. B
80-pin
SCSI I/O
Connector
Pin 1
J2
J6
Note. This drive model plugs directly into a backplane connec-
tor and therefore uses no cables.
Figure 3e. Drive model “WC” or “DC” with single 80-pin I/O
and power connector
Cheetah 4LP Installation Guide, Rev. B
29
Providing adequate cooling
The enclosure design must ensure adequate cooling for the
drive. The maximum ambient temperature is 50°C.
The drive’s product manual (83329120) describes how to evalu-
ate the air-flow design. The evaluation consists of ensuring that
the case temperature of certain critical components remains
within acceptable limits during drive operation.
We recommend orienting the drive or directing the air flow in a
way that creates the least amount of air-flow resistance while
providing air flow above the circuit boards and around the head
and disc assembly (HDA). Also, choose the shortest possible
path between the air inlet and exit. This minimizes the distance
traveled by air that is heated by the drive and by other nearby
heat sources.
Figure 4 shows two design approaches with one or more fans
used to generate air flow. The air-flow patterns can be created
by the fans either pushing or drawing air. The overall flow pattern
can be directed from front to back, back to front, or side to side.
30
Cheetah 4LP Installation Guide, Rev. B
Kühlung des Systems
Die Gehäusekonstruktion muß eine ausreichende Kühlung des
Laufwerkes gewährleisten. Die Umgebungstemperatur darf
maximal 50°C betragen.
Die Produkthandbuch Cheetah 4LP (Dokument 83329120)
enthalten Anweisungen zur Beurteilung der Luftstromkonstruk-
tion. Die Beurteilung muß sicherstellen, daß sich die Gehäuse-
temperatur bestimmter kritischer Komponenten bei
Laufwerkbetrieb innerhalb zugelassener Grenzen hält.
Wir empfehlen, das Laufwerk so zu orientieren oder den Luft-
strom so zu lenken, daß der geringste Luftstromwiderstand
erzeugt wird und gleichzeitig ein Luftstrom über den Platinen
und um die Kopf- und Festplatteneinheit (HDA) gegeben ist.
Wählen Sie einen möglichst kurzen Weg zwischen Lufteinlaß
und -auslaß. Dadurch wird die Strecke, die die vom Laufwerk
und anderen nahegelegenen Hitzequellen aufgewärmte Luft
zurücklegt, auf ein Minimum beschränkt.
Abbildung 4 zeigt zwei Konstruktionsmöglichkeiten, bei denen
ein oder mehrere Lüfter den Luftstrom erzeugen. Der Luftstrom-
verlauf wird durch die Lüfter gesteuert, die entweder Luft einbla-
sen oder abziehen. Generell kann der Luftstrom entweder von
vorne nach hinten oder von hinten nach vorne verlaufen.
Cheetah 4LP Installation Guide, Rev. B
31
.
Above unit
Under unit
Note. Air flows in the direction shown (back to front)
or in reverse direction (front to back)
Above unit
Under unit
Note. Air flows in the direction shown or
in reverse direction (side to side)
Figure 4. Suggested air flow
Abbildung 4. Empfohlener Luftstromverlauf
32
Cheetah 4LP Installation Guide, Rev. B
Mounting the drive and connecting cables
Do not touch the connector pins or any components on the con-
trol board without observing static-discharge precautions.
Always handle the drive by the frame only.
The drive may be mounted in any orientation (horizontally, verti-
cally, and any combination thereof); however, you must ensure
that the drive receives adequate air flow for cooling.
1. Mount the drive to the host system’s chassis using four 6-32
UNC screws. Two mounting holes are in each side of the
drive and there are four mounting holes in the bottom of the
drive.
The maximum length that the screws should extend into the
chassis mounting holes is 0.15 inch (3.81 mm), measured
from the outer surface of the chassis. Tighten the screws
down evenly. Do not over-tighten or force the screw if it
does not seem to screw in easily, because this means the
threads are not properly aligned. In this case, back the
screw out and try again.
Installation des Laufwerkes
und Anschluß der Kabel
Beachten Sie beim Handhaben und Anfassen der Anschlußstifte
und Komponenten die Vorsichtsmaßnahmen zur Verhinderung
statischer Aufladung. Fassen Sie das Laufwerk nur am Rahmen
an.
Das Laufwerk kann in beliebiger Orientierung (horizontal, ver-
tikal oder schräg) installiert werden; jedoch muß dafür gesorgt
werden, daß ein ausreichender Luftstrom zur Kühlung des Lauf-
werkes vorhanden ist.
Cheetah 4LP Installation Guide, Rev. B
33
1. Befestigen Sie das Laufwerk mit vier 6-32-UNC-Schrauben
am Gehäuse des Host-Systems. Die beiden Seiten des
Laufwerkes sind mit jeweils zwei Befestigungslöchern
versehen, die Unterseite des Laufwerkes weist vier weitere
Befestigungslöcher auf.
Gemessen von der Außenfläche des Gehäuses dürfen die
Schrauben maximal 3,81 mm in die Befestigungslöcher des
Gehüuses hineinragen. Die Schrauben müssen gleich-
mäßig, jedoch nicht zu fest, angezogen werden. Wenn sich
eine Schraube nicht ohne Widerstand einschrauben läßt,
sind die Gewinde nicht korrekt aneinander ausgerichtet. In
diesem Fall die Schraube nicht in das Gewindeloch
forcieren, sondern die Schraube herausnehmen und erneut
in das Gewindeloch einführen.
2. Verify that all connections between the drive and the host
system are correctly installed.
2. Prüfen Sie, ob alle Verbindungen zwischen dem Laufwerk
und dem Host-System korrekt hergestellt sind.
3. Verify that you have correctly installed jumpers.
3. Stellen Sie sicher, daß die Kennungsbrücken installiert sind.
4. Connect the SCSI cable into the drive’s SCSI connector.
Take care not to stretch or crimp this cable, and do not
block the system’s cooling air flow with the cable.
The drive receives DC power through a 4-pin connector
mounted next to the SCSI connector. The output of a power
supply must meet SELV (safety extra low voltage) as
34
Cheetah 4LP Installation Guide, Rev. B
defined in IEC 950. Figure 5 provides the pin information for
the DC power connector. To connect the DC power cable to
the drive, simply insert the cable end into the drive’s DC
power connector.
4. Schließen Sie das SCSI-Kabel an den SCSI-Steckverbinder
des Laufwerkes an. Das Kabel darf nicht gedehnt oder
gedrückt werden und es darf den Luftstrom zur Kühlung des
Systems nicht behindern.
Das Laufwerk wird über einen 4-poligen, neben dem SCSI-
Anschluß befestigten Steckverbinder mit Gleichstrom ver-
sorgt. Der Ausgang eines Netzteils muß SELV (safety extra
low voltage) nach IEC 950 entsprechen. Abbildung 5 zeigt
die Steckerbelegung für den Gleichstromanschluß. Zum
Anschluß des Gleichstromkabels an das Laufwerk das
Kabelende in den Gleichstromanschluß des Laufwerkes
stecken.
Pin
1
Power
Pin Gleichstrom
+12V
1
2
3
4
+12 V
2
+12V return
+ 5V return
+ 5V
+12 V Rückleitung
+ 5 V Rückleitung
+ 5 |