Seagate ST336605LW/LC/LCV Reliability and service, Mean time between failure Mtbf, Service life

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Cheetah 73LP 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 73LP disc drives by ensuring that the drive receives adequate cool- ing. Section 6.0 provides recommended air-flow information, temperature measurements, and other informa- tion, which you can use to enhance the service life of the drive.

5.2.1Mean time between failure (MTBF)

The production disc drive achieves an MTBF of 1,200,000 hours when operated in an environment that ensures the case temperatures specified in Section 6.4.1 are not exceeded. Short-term excursions up to the specification limits of the operating environment will not affect MTBF performance. Operating the drive at case temperatures above these values will adversely affect the drive’s ability to meet specifications. See Section 6.4, “Environmental limits”.

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

The following expression defines MTBF:

MTBF per measurement period = Estimated power-on operating hours in the period

Number of drive failures in the period

Estimated power-on operating hours means power-on hours per disc drive times the total number of disc drives in service. Each disc drive must have accumulated at least nine months of operation. Data is 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

•Operating at nominal voltages

•System provides adequate cooling to ensure the case temperatures specified in Section 6.4.1 are not exceeded.

Drive failure means any stoppage or failure to meet defined specifications 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 is required.

5.2.3Service life

The drive has a useful service life of five years. Depot repair or replacement of major parts is permitted during the lifetime.

5.2.4Service philosophy

Special equipment is required to repair the drive HDA. To achieve the above service life, repairs must be per- formed only at a properly equipped and staffed Seagate 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. There are not spare parts available for this drive. The 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 because users cannot purchase individual parts for the drive.

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Contents ST373405LW/LWV/LC/LCV ST336605LW/LC/LCV Page ST373405LW/LWV/LC/LCV ST336605LW/LC/LCV Page Revision status summary sheet Revision Date Writer/Engineer Sheets AffectedPage Contents Defect and error management InstallationSeagate Technology support services Interface requirementsList of Figures Cheetah 73LP Product Manual, Rev. E ViiPage Scope Cheetah 73LP family drive ST373405LW shownCheetah 73LP Product Manual, Rev. E Applicable standards and reference documentation Australian C-Tick Korean MICTaiwanese Bsmi General description Cheetah 73LP family drive Cheetah 73LP Product Manual, Rev. E Standard features Media characteristicsPerformance ReliabilityFactory installed accessories Options factory installedAccessories user installed Unformatted and formatted capacitiesPerformance characteristics Ultra2 Scsi Ultra3 Scsi Start/stop timePrefetch/multi-segmented cache control Cheetah 73LP Product Manual, Rev. E Cache operation Caching write dataPrefetch operation Reliability specifications Reliability and service Preventive maintenanceService life Service philosophy7 S.M.A.R.T Controlling S.M.A.R.TPerformance impact MillisecondsReporting control Determining rateState of the drive prior to testing DST Failure DefinitionImplementation Invoking DSTShort and extended tests Short test Function Code 001bExtended test Function Code 010b Log page entriesCheetah 73LP Product Manual, Rev. E Product warranty ShippingProduct repair and return information Cheetah 73LP Product Manual, Rev. E Physical/electrical specifications AC power requirementsDC power requirements Power sequencing Conducted noise immunity3 12 V Current profile Typical ST336605 drive +12 V current profile Typical ST336605 drive +5 V current profile Amperes 000 900 800 700 600 Temperature Cheetah 73LP Product Manual, Rev. E Environmental limitsRelative humidity Effective altitude sea levelShock and vibration ShockRecommended mounting Air cleanliness VibrationAcoustics LW and LWV mounting configuration dimensions LC and LCV mounting configuration dimensions Defect and error management Drive error recovery proceduresDrive internal defects Scsi systems errors Installation Configure drive optionsFormatting Drive ID/option select headerDo not install jumpers retain cover J5 jumper header on LW/LWV models only J2 option select header Cheetah 73LP Product Manual, Rev. E Function description Does not apply to LC/LCV modelDrive orientation CoolingCheetah 73LP Product Manual, Rev. E Drive mounting GroundingCheetah 73LP Product Manual, Rev. E Interface requirements Scsi interface messages supportedScsi interface commands supported Cheetah 73LP Product Manual, Rev. E Cheetah 73LP Product Manual, Rev. E Inquiry Vital Product data Mode Sense data DEF CHG Cheetah 73LP Product Manual, Rev. E Condition/feature supported by DC cable and connector 2 REQ/ACK offsetPhysical interface Pin Power Scsi interface physical description Scsi interface cable requirementsMating connectors Mating connectors for LW and LWV model drivesMating connectors for LC and LCV model drives ST373405LC/LCV and ST336605LC/LCVCheetah 73LP Product Manual, Rev. E Right-angle to Pcba connectors Scsi ID650±.005 155 100 346 Front View GND +DBP1 62Cheetah 73LP Product Manual, Rev. E REQ +REQ LVD output characteristics Electrical descriptionMultimode-SE and LVD alternatives General cable characteristics Single-ended drivers/receiversCables for low voltage differential drivers/receivers Terminator requirementsLC and LCV drives Disc drive Scsi timing Spindle status Command status LED status Drive activity LEDCheetah 73LP Product Manual, Rev. E Seagate Technology support services Online Services Automated ServicesPresales Support Technical SupportCustomer Service CSO USA/Canada/Latin America Support ServicesEuropean Support Services Africa/Middle East Support Services Asia/Pacific Support ServicesCall Center Toll-free Direct dial Cheetah 73LP Product Manual, Rev. E Index Cheetah 73LP Product Manual, Rev. E Cheetah 73LP Product Manual, Rev. E Scam Scsi Scsi ID 80Cheetah 73LP Product Manual, Rev. E
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