Seagate ST43400N/ND User manual

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Elite Disc Drive
ST43400N/ND
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User’s Manual

ii
Contents
Preface .................................................................................................... iii
Electrostatic discharge protection........................................................ iii
Important safety information and precautions...................................... iv
Technical support services.................................................................. vi
Section 1. General description ................................................................ 1
Section 2. Installation .............................................................................. 7
Section 3. Operation ............................................................................... 33
Section 4. Parts data............................................................................... 37
Section 5. Maintenance........................................................................... 39
© 1992 Seagate Technology, Inc. All rights reserved
Publication Number: 83327630, Rev. A
Seagate®, Seagate Technology®, and the Seagate logo are registered
trademarksofSeagateTechnology,Inc.EliteTM,SeaFAXTM,SeaFONETM,and
SeaBOARDTM are trademarks of Seagate Technology, Inc. Other product
names are registered trademarks or trademarks of their owners.
No part of this publication may be reproduced in any form without written
permission from Seagate Technology, Inc.

ST43400N/ND User’s Manual iii
Preface
This manual contains information for users of the Seagate ST43400N and
ST43400ND Elite disc drives employing the SCSI interface. It provides instal-
lation, operation, and maintenance information. This manual also lists the part
numbers for options and accessories available for these drives. Additional
information is available in the reference manual (publication 83327640).
Electrostatic discharge protection
Caution. Removal of circuit boards by personnel not performing 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
somedevicessuch as metal-oxide semiconductors are extremelysensitive,
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
dischargeofachargedconductororbyexposuretothestaticfieldssurround-
ing charged objects. To avoid damaging drive electronic assemblies, ob-
serve 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 (refer to accessories
in Section 4 for part numbers). Connection may be made to any grounded
metalassembly.Asageneralrule,rememberthatyouandthedriveelectron-
ics 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.

iv
Important safety information and precautions
Caution. Use forced-air ventilation when bench-testing the drive to ensure
proper cooling of drive components.
Usepropersafety and repair techniques for safe,reliableoperation of this unit.
Service should be done only by qualified persons. We recommend the proce-
dures in this manual as effective ways of servicing the unit. Some procedures
require the use of special tools. For proper maintenance and safety, you must
use these tools as recommended.
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
endangeryouorothers.Thecautionspointoutconditionsorpracticesthatmay
damage the unit, possibly making it unsafe for use.
Youmustalsounderstandthatthesewarningsandcautionsarenotexhaustive.
We cannot possibly know, evaluate, and advise you of all the ways in which
maintenance might be performed or the possible risk of each technique.
Consequently, we have not completed any such broad evaluation. If you use a
non-approvedprocedureortool,firstensurethatthemethodyouchoosewillnot
risk either your safety or unit performance.
Always observe the following warnings and precautions:
• Perform all maintenance by following the procedures in this manual.
• Follow all cautions and warnings in the procedures.
• Use sound safety practices when operating or repairing the unit.
• Usecautionwhentroubleshootingaunitthathasvoltagespresent.Turnoff
power to the unit before servicing it.
• Wear safety shoes when removing or replacing heavy parts.
• Provideameanstoisolatethedrivefromthemainpowerincaseoffireorother
emergency.
• Ensure that the internal temperature of the rack or cabinet does not exceed
thelimitsdefinedforthedrive,whenthedriveismountedinanequipmentrack
or cabinet. When units are stacked vertically, pay special attention to the top
where temperatures are usually highest.
• Follow the precautions listed above in “Electrostatic discharge protection.”
• Do not remove any circuit boards from the drive chassis. Return the entire
drivefordepotrepairifanycircuitboardisdefective.Removalofcircuitboards
by personnel not performing depot repair will damage components and may
void the warranty.

ST43400N/ND User’s Manual v
• Do not remove the head and disc assembly (HDA) from the drive chassis.
Return the entire drive for depot repair if the HDA is defective.
• Donotattempttodisassemblethe HDA.Itisnot fieldrepairable.Ifthe 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 operated in
accordancewithUL1950,IEC950,EN60950,CSAC22.2950,andVDE0806.
Refer to section 2 for information about installation.
If you do not use a Seagate power supply, ensure that the supply meets the
specifications in this manual and is designed to be used in accordance with
UL1950, IEC950, EN60950, CSA C22.2 950, and VDE0806.
Seagatetakesall reasonable steps to ensure thatitsproducts are certifiable to
currently accepted standards. Typical applications of these disc drives include
customerpacking and subsystem design. Safetyagenciesconditionally certify
component parts, such as the Elite 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 compli-
ance in their end-use products and for certifying where required by law. A
necessary part of meeting safety requirements is the provision for overcurrent
protection on drive SELV supply voltages.
ThisunitisacomponentassemblyandassuchisnotmeanttocomplywithFCC
orsimilarnationalrequirementsasastand-aloneunit.Engineeringradiatedand
conducted emissions test results are available through the Seagate Safety
Department to assist the subsystem designer.

vi
Technical support services
Seagate Technology provides technical support literature and diagnostic utili-
ties to authorized distributors. Please contact your dealer for technical support
and installation troubleshooting. Product technical support is available for all
Seagate products by calling the SeaFAX, SeaFONE, or SeaBOARD services.
These are toll calls if you dial from outside of the number’s local dialing area.
SeaFAX: [phone]
You can use a Touch-Tone telephone to access Seagate’s automated FAX
delivery system and select technical support information by return FAX. This
service is available twenty-four hours a day, seven days a week.
SeaFONE: [phone]
The enhanced phone system provides recorded technical information on
selectedSeagateproductswhileyouareonhold.Technicalsupportspecialists
are available to answer questions from 8:00 A.M. to 5:00 P.M. PST, Monday
throughFriday.Recordingsareaccessibletwenty-fourhoursaday,sevendays
a week.
SeaBOARD:
The Seagate Technical Support Bulletin Board System (BBS) is available
twenty-fourhoursaday,sevendaysaweek.Amodemisrequiredtoaccessthis
service. The communications software must be set for eight data bits no parity
and one stop bit (8N1). With this service you can access:
• Specifications and jumper configurations for all Seagate products
• Reprints of Seagate documentation
• A directory of information and helpful utilities that you can download to your
own computer
Location Telephone Number Maximum Baud Rate
United States/Canada [phone] 9600
England 44-62-847-8011 9600
Germany 49-89-140-9331 2400
Singapore 65-227-2217 9600
Australia 61-2-756-2359 9600
Note.Thisisatollcallifyoudialfromoutsideofthenumber’slocaldialingarea.

Section 1. General description
TheSeagateST43400N/NDElite3disc drives are high speed, random access
digitaldatastoragedevices.TheycommunicatewithaninitiatorusingtheSmall
Computer System Interface (SCSI). The drive is shown in Figure 1, and its
specifications are listed in Table 1 on the following page.
Thedriveisacomponentfor installation in an enclosure designed for thedrive.
The enclosure design must ensure adequate cooling for the drive, and it must
address the requirements for grounding and for shielding of emissions. The
referencemanual(publication83327640)presentsguidelinesfordesigningthe
enclosure, but the design is your responsibility.
1
Figure 1. The ST43400N/ND disc drive
Control
Board Power
Board
Optional
Bezel
Chassis
DC Power
Connector
Spindle Sync
Connector
Option
Jumpers
I/O
Connector
Option
Jumpers
Option
Jumpers
Head and Disc
Assembly (HDA)
Pin 1

2
Table 1. Drive specifications
Characteristics Conditions Specifications
Size Dimensions See “Space requirements”
in section 2
Weight (drive only) 3.6 kg (8.0 lb)
Weight (power supply only) 2.3 kg (5.0 lb)
Interface Fast SCSI-2
Recording Total capacity 3,554,871,600 bytes
(unformatted)
Bytes per track
(unformatted)
Inner track 49,000 bytes
Outer track 72,800 bytes
Formatted capacity*
(256-byte sectors) 2,538,290,688 bytes
(512-byte sectors) 2,916,687,360 bytes
(1,024-byte sectors) 3,150,686,208 bytes
Number of discs 11
Recording heads 21
Servo heads 1
Physical heads per surface 1
Cylinders per head/disc assy 2,738 (includes 2 spares)
Cylinders available to user 2,736
Spare cylinders 1
System cylinders 1
Diagnostic cylinders 1
Spare sectors per cylinder 6
Modulation 1,7 code
* Excluding spare sectors, spare cylinders, diagnostic cylinders, and system cylin-
ders.
continued

General description 3
continued from previous page
Characteristics Conditions Specifications
SCSI transfer rate, burst 10.0 Mbytes/sec max
Seek time
(time required to move heads
to a different track address—
excluding SCSI I/O overhead) Typical full 23.5 msec
Typical average 11.5 msec
Typical one-track 1.7 msec
Typical access times Write Read
Typical single track
seek msec 1.7 0.9
Average seek msec 11.5 10.5
Maximum seek msec 23.5 22.5
Latency
(time required to reach a
particular track address after
head positioning is complete) Average 5.55 msec
(disc rotation
at 5400 RPM)
Maximum 11.17 msec
(disc rotation
at 5373 RPM)
Start time** 30 sec max
Stop time 30 sec max
** Following the power sequence delay, once DC power is applied and start
conditions are present.

4
The drive contains all the circuits and mechanical devices necessary to record
data on and recover it from its discs. The drive requires DC voltage input from
anexternalpower supply, which receives its ACinputpower from the site main
power source. A power supply and DC power cable are available accessories.
The drive consists of a head and disc assembly (HDA) and two circuit boards,
mounted on a common chassis. The circuit boards contain the electronics
requiredfordriveoperation.TheHDAisasealedunitcontainingtheelectrome-
chanical components used for data retrieval and storage. These components
include the discs, spindle, drive motor, actuator, heads, and preamplifiers.
The 11 discs provide the recording medium for the drive. These discs are
mountedonaspindle,andthespindleiscoupleddirectlytothedrivemotor.The
drivemotor rotates the discs at 5400 RPM and produces a circulation of air
within the sealed HDA.
The built-in SCSI controller directs all drive functions, receives commands
from the initiator (host computer), interprets them, and then transfers the
necessary commands to the drive. The controller therefore allows the
initiator to start an operation and then disconnect to service another device.
Refer to the reference manual for a description of interface functions.
Alldriveoperationsarerelatedto data recovery and storage (normally referred
toasreadingandwriting).Theactualreadingandwritingisperformedbyheads
that are positioned over the rotating discs’ recording surfaces. There is one
head for each data surface. The heads are positioned in such a way that data
is written in concentric tracks around the disc surfaces (see Figure 2).
Before any read or write operation can be performed, the controller must
instruct the drive to position the heads over the desired cylinder (called
seeking)andtousetheheadlocatedoverthesurface(headselection)where
the operation is to be performed.
Theheadsaremountedontheactuator,andtheactuatormovestheheadsover
the rotating discs. There are 22 heads; a servo head to sense actuator
positioningand21dataheadsusedfordatatransferstoandfromthediscs.The
actuator has a voice coil that moves in a permanent magnetic field in response
to signals from the servo positioning circuitry.Thevoice coil moves the heads in
an arc across the rotating discs.
When the drive is not powered on, the heads rest on the disc surface in a
preassignedlandingzonelocatedbeyondthedatazone.Theactuatorautomati-
cally latches in this position to protect the drive in the event that it is moved or
shipped. When the drive is activated to bring the discs up to speed, the heads
fly on a cushion of air close to the disc surface.

General description 5
Initiator
Unit
Selection
Logic
Read/Write
Logic
Head
Selection
Logic
Seek
Logic
Track
Orientation
Logic
Error
Detection
Logic
I/0 Lines
SCSI
Controller
Power Supply
Discs
Heads
Data recorded in
concentric tracks
Figure 2. Drive functional block diagram
After arriving at the data track and selecting a head, the controller locates the
portion of the track where the data is to be read or written. This is called track
orientation. Signals from the drive indicate the beginning of each track. The
controllerusesthesesignalsto determine the position oftheheadonthetrack.
Whentheheadisabovethedesiredtracklocation,thecontrollercommandsthe
drive to actually read or write the data. During a read operation, the drive
retrieves data from the discs, processes it, and transmits it to the controller.
Duringawriteoperation, the drive receives data from thecontroller,processes
it, and stores it on the discs.
The drive can also recognize certain errors that may occur during its
operation.Whenanerrorisdetected,itisindicatedtotheinitiatorbytheSCSI
controller.

Section 2. Installation
The information contained in this section describes installation and initial
checkout of the drive.
Site requirements
The site requirements considered are environment, airflow, space, power,
grounding, and interface.
Environmental requirements
All environmental requirements for the drive are listed in Table 2 below.
Table 2. Drive environmental requirements
Conditions Specifications
Operating environment
Temperature Range of 5oC to 50oC (41oF to 122oF) with a
maximum change of 20oC (36oF) per hour
Humidity Range of 5% to 95% relative
A maximum wet bulb temperature of 26oC (79oF)
no condensation
Barometric pressure -305 m to 3,048 m (-1,000 ft to 10,000 ft);
104 kPa to 69 kPa (30 in Hg to 20 in Hg)
Non-operating environment
(unpacked)
Temperature Range of -40oC to 60oC (-40oF to 140oF) with a
maximum change of 20oC (36oF) per hour
Humidity Range of 5% to 95% relative
A maximum wet bulb temperature of 26oC (79oF)
no condensation
Barometric pressure -305 m to 12,192 m (-1,000 ft to 40,000 ft);
104 kPa to 19 kPa (30 in Hg to 6 in Hg)
Storage/transit environment
(packed)
Temperature Range of -40oC to 60oC (-40oF to 140oF) with a
maximum change of 20oC (36oF) per hour
Humidity Range of 5% to 95% relative
Barometric pressure -305 m to 12,192 m (-1,000 ft to 40,000 ft);
104 kPa to 19 kPa (30 in Hg to 6 in Hg)
7

8
Airflow requirements
Theenclosuredesignmustensureadequatecoolingforthedrive.Notethatthe
fan in the power supply cools only the power supply’s internal parts.
The drive’s product specification (document 64403601) describes how to
evaluatetheairflowdesign.Theevaluationconsistsofensuringthatthecase
temperatures of certain critical components remain within acceptable limits
during drive operation.
Werecommend orienting the driveor directing the airflowin a way thatcreates
the least amount of airflow resistance while providing airflow 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 3 shows two design approaches with one or more fans used to
generateairflow.Theairflowpatternscanbecreatedbythefanseitherpushing
ordrawing air. The overallflow pattern can bedirected from front toback, back
to front, or side to side.

Installation 9
Above unit
Under unit
Note. Air flow in the direction shown (front to back)
or in reverse direction (back to front)
Above unit
Under unit
Note. Air flow in the direction shown or
in reverse direction (side to side)
Figure 3. Suggested airflow

10
Figure 4. Mounting orientations
Space requirements
The drive is designed to be mounted in one of the three orientations shown
inFigure4.Thedrivemaybemountedonitsbaseoroneitherside.Mounting
orientations other than those shown are not permitted. The physical dimen-
sions of the drive and power supply are shown in Figure 5. The drive itself
weighs 3.6 kg (8.0 lb).
For details about designing an enclosure to match the drive mounting dimen-
sions, refer to the drive’s product specification.
Up
Up
Up

Installation 11
83 mm
3.25 in
204.72 mm
8.06 in max
70 mm
2.75 in
141 mm
5.57 in
147 mm
5.75 in
Drive
Power Supply
202 mm
8.00 in
Figure 5. Dimensions of the drive and power supply

12
Power requirements
Thevoltageandcurrent requirements for a single drive atcylinder0are shown
in Table 3.
Table 3. Single drive voltage and current requirements
Current without Internal Current with Internal
Terminator Terminator
Seeking Contin- Seeking Contin-
and uous and uous
Voltage Idle Reading Reading Idle Reading Reading
SCSI single-ended interface
+5 V 1.87A 1.91 A 2.00A 1.90A 1.96A 2.09A
+12V 1.57A 1.92 A 1.56A 1.57A 1.90A 1.56A
Watts 28.19W 32.59 W 28.72W 28.34W 32.60W 29.17W
SCSI differential interface
+5 V 2.32A 2.63 A 2.75A 2.45A 2.77A 2.85A
+12V 1.63A 1.88 A 1.64A 1.63A 1.88A 1.66A
Watts 31.21W 35.71 W 33.40W 31.81W 36.41W 34.17W
Without Internal With Internal
Terminator Terminator
Maximum Current Limits +5 V +12 V +5 V +12 V
SCSI single-ended interface
Maximum operating current* 2.06A 3.09A 2.37A 3.04A
Average idle current 1.84A 1.92A 1.96A 1.92A
Maximum starting current* 2.06A 3.98A 2.37A 3.98A
Maximum seek current* 1.89A 2.12A 2.16A 3.19A
SCSI differential interface
Maximum operating current* 2.98A 2.88A 3.48A 3.17A
Average idle current 2.11A 1.85A 2.45A 1.63A
Maximum starting current* 2.98A 3.98A 3.48A 4.60A
Maximum seek current* 2.31A 2.13A 3.48A 3.17A
*Instantaneous +12 V current peaks will exceed these values by up to 0.8 A.

Installation 13
AC power requirements for the optional Seagate power supply are listed in
Table 4 below. Conversion to the different line voltages is explained in the
installationprocedures.
Table 4. Power supply AC power requirements
Nominal Values
Specifications 100–120 VAC 208–240 VAC
Voltage range 85 to 132 V 175 to 264 V
Nominal line frequency 50/60 Hz 50/60 Hz
Frequency range 48.0 to 62.0 Hz 48.0 to 62.0 Hz
Phase requirements Single phase Single phase
Power consumed* 71.5 W 69.5 W
Line current* 0.90 A 0.50 A
Power factor* 0.55 0.47
*Measured at nominal values when discs are rotating and carriage is track-following.
Grounding requirements
Asafety groundmustbeprovided bythesite ACpowersystem.The greenwire
(orgreenwirewithyellowstripe)intheACpowercordprovidesthesafetyground
connection between the power supply and the site AC power system. The site
AC power system must provide the safety ground to earth ground connection.
All site AC power connection points, including convenience outlets for test
equipment, must be maintained at the same safety ground potential.
Interface requirements
An important part of site preparation is planning the layout and routing of I/O
cables.All drives and other SCSI devices are connected together and to the
host with an I/O cable.TheSCSIbuscanhaveup to eight devices attached to
it as shown in Figure 6. The I/O cabling scheme used is called a daisychain.
Each end of the SCSI bus must be terminated.

14
SCSI
Device
0
SCSI
Device
1
SCSI
Device
2
SCSI
Device
3
Term
SCSI
Device
7
SCSI
Device
6
SCSI
Device
5
SCSI
Device
4
Term
Figure 6. SCSI bus configuration
A connector (J06) at the back of the drive accepts the I/O cable that connects
it to the system. The daisychain cable is a continuous unshielded cable having
one connector for each drive it connects to.
Refer to the reference manual (publication 83327640) for guidelines on I/O
cabling.Theseguidelinesdiscusstheuseofunshieldedcablinginsidecabinets
and shielded cabling running between cabinets. They also contain information
about constructing continuous daisychain cabling (including part numbers for
the required cabling components).
Table5onthefollowingpageshowsthepinassignments and signal names for
theunshieldedsingle-endedI/Ocable.Table6showsthepinassignmentsand
signalnamesfortheunshieldeddifferentialI/Ocable.Detailedinformationabout
interface lines is provided in the reference manual.

Installation 15
Table 5. Unshielded single-ended I/O cabling
Signal Name Pin Number
DB- (0) 2
DB- (1) 4
DB- (2) 6
DB- (3) 8
DB- (4) 10
DB- (5) 12
DB- (6) 14
DB- (7) 16
DB- (P) 18
GROUND 20
GROUND 22
GROUND 24
TERMPWR 26
GROUND 28
GROUND 30
ATN- 32
GROUND 34
BSY- 36
ACK- 38
RST- 40
MSG- 42
SEL- 44
C/D- 46
REQ- 48
I/O- 50
Notes:
1. All odd pins except 25 must be connected to ground. Pin 25 is open.
2. A minus sign indicates active low.