Seagate ST336705LW/LC Reliability and service, Mean time between failure, Preventive maintenance

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Cheetah 36XL Product Manual, Rev. E

error (15h) is reported with a Medium error (3h) or Hardware error (4h) reported in the Sense Key. This is an unrecoverable seek error. Unrecoverable seek errors are classified as failures for MTBF calculations. Refer to the SCSI Interface Product Manual, part number 75789509, for Request Sense information.

5.2Reliability and service

You can enhance the reliability of Cheetah 36XL disc drives by ensuring that the drive receives adequate cool- ing. Section 6.0 provides temperature measurements and other information that may be used to enhance the service life of the drive.

5.2.1Mean time between failure

The production disc drive shall achieve an MTBF of 1,200,000 hours when operated in an environment that ensures the case temperatures are not exceeded. Short-term excursions up to the specification limits of the operating environment will not affect MTBF performance. Continual or sustained operation at case tempera- tures above the values specified in Section 6.4.1 may degrade product reliability.

The MTBF target is specified as device power-on hours (POH) for all drives in service per failure.

Estimated power-on operating hours in the period

=

MTBF per measurement period

 

 

 

Number of drive failures in the period

Estimated power-on operation hours means power-up hours per disc drive times the total number of disc drives in service. Each disc drive shall have accumulated at least nine months of operation. Data shall be calculated on a rolling average base for a minimum period of six months.

MTBF is based on the following assumptions:

•8,760 power-on hours per year.

•250 average on/off cycles per year.

•Operations at nominal voltages.

•Systems will provide adequate cooling to ensure the case temperatures specified in Section 6.4.1 are not exceeded.

Drive failure means any stoppage or substandard performance caused by drive malfunction.

A S.M.A.R.T. predictive failure indicates that the drive is deteriorating to an imminent failure and is considered an MTBF hit.

5.2.2Preventive maintenance

No routine scheduled preventive maintenance shall be required.

5.2.3Service life

The drive shall have a useful service life of five years. Depot repair or replacement of major parts is permitted during the lifetime (see Section 5.2.4)

5.2.4Service philosophy

Special equipment is required to repair the drive HDA. In order to achieve the above service life, repairs must be performed only at a properly equipped and staffed service and repair facility. Troubleshooting and repair of PCBs in the field is not recommended, because of the extensive diagnostic equipment required for effective servicing. Also, there are no spare parts available for this drive. Drive warranty is voided if the HDA is opened.

5.2.5Service tools

No special tools are required for site installation or recommended for site maintenance. Refer to Section 5.2.4. The depot repair philosophy of the drive precludes the necessity for special tools. Field repair of the drive is not practical since there are no user purchasable parts in the drive.

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Contents Cheetah 36XL Family ST336705LW/LC ST318405LW/LC ST39205LW/LC Page Cheetah 36XL Family ST336705LW/LC ST318405LW/LC ST39205LW/LC Page Revision status summary sheet Revision Date Writer/Engineer Sheets AffectedPage Contents Seagate Technology support services Defect and error managementInstallation Interface requirementsList of Figures Cheetah 36XL Product Manual, Rev. E ViiPage Scope Cheetah 36XL family drive ST336705LC shownCheetah 36XL Product Manual, Rev. E Applicable standards and reference documentation Taiwanese Bsmi Australian C-TickKorean MIC General description Cheetah 36XL family drive Performance Cheetah 36XL Product Manual, Rev. E Standard featuresMedia characteristics ReliabilityFormatted capacities Factory installed accessoriesOptions factory installed Programmable drive capacityPerformance characteristics Prefetch/multi-segmented cache control Ultra2 Scsi Ultra160 ScsiStart/stop time Cache operation Caching write dataPrefetch operation Cheetah 36XL Product Manual, Rev. E Cheetah 36XL Product Manual, Rev. E Reliability specifications Service life Reliability and servicePreventive maintenance Service philosophy7 S.M.A.R.T Controlling S.M.A.R.TDetermining rate Performance impactReporting control Predictive failuresImplementation State of the drive prior to testingDST Failure Definition Invoking DSTExtended test Function Code 010b Product warrantyShort test Function Code 001b Log page entriesProduct repair and return information Cheetah 36XL Product Manual, Rev. E DC power requirements Physical/electrical specificationsAC power requirements 3 12 V Current profile Power sequencingConducted noise immunity Typical ST336705 drive +12 V current profile Typical ST39205 drive +12 V current profile TypicalST318405 drive +5 V current profile Power dissipation ST336705 Cheetah 36XL Product Manual, Rev. E ST318405 Os per SecondEnvironmental limits TemperatureST39205 Shock and vibration Relative humidityEffective altitude sea level ShockPackage size Packaged/product weight Drop height Recommended mounting Acoustics Air cleanlinessVibration LW mounting configuration dimensions LC mounting configuration dimensions Drive internal defects Defect and error managementDrive error recovery procedures Scsi systems errors Formatting InstallationConfigure drive options Drive ID/option select headerDo not install jumpers retain cover J5 jumper header on LW model only J2 option select header Cheetah 36XL Product Manual, Rev. E Function description Does not apply to LC modelsDrive mounting Drive orientationCooling GroundingInterface requirements Scsi interface messages supportedScsi interface commands supported Cheetah 36XL Product Manual, Rev. E Commands supported by Cheetah 36XL family drive Mode Sense data Inquiry Vital Product dataCheetah 36XL Product Manual, Rev. E Mode Sense Data Cheetah 36XL Product Manual, Rev. E Mode sense data, ST318405 values Bytes Cheetah 36XL Product Manual, Rev. E Mode sense data, ST39205 values Bytes Cheetah 36XL Product Manual, Rev. E Condition/features supported Physical interface DC cable and connector2 REQ/ACK offset Pin Power Scsi interface physical description Scsi interface cable requirementsMating connectors for LC model drives Mating connectorsMating connectors for LW model drives ST336705LC, ST318405LC and ST39205LCRight-angle to Pcba connectors Scsi IDNonshielded 68 pin Scsi device connector used on LW drives Nonshielded 80 pin Scsi SCA-2 connector, used on LC drives GND +DBP1 Charge 68Cheetah 36XL Product Manual, Rev. E Multimode-SE and LVD alternatives Multimode signalsElectrical description Output characteristics Input characteristicsLow voltage differential I/O circuits General cable characteristicsTerminator requirements Terminator power LW drives LC drivesDisc drive Scsi timing Drive activity remote LED signal status Cheetah 36XL Product Manual, Rev. E Presales Support Seagate Technology support services Online ServicesAutomated Services Technical SupportEuropean Support Services Customer Service CSOUSA/Canada/Latin America Support Services Call Center Toll-free Direct dial Africa/Middle East Support ServicesAsia/Pacific Support Services Cheetah 36XL Product Manual, Rev. E Index Symbols Cheetah 36XL Product Manual, Rev. E LED PCB System chassis Page
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