seagate ST173404FC, ST173404FCV Product Manual
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Cheetah 73FC Disc Drive
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ST173404FC/FCV
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Product Manual, Volume 1
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Cheetah 73FC Disc Drive
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ST173404FC/FCV
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Product Manual, Volume 1
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© 2000 Seagate T echnology, LLC All rights reserved
August 2000
Publication number: 83329482, Rev. C
Seagate , Seagate Technology, and the Seagate logo are registered trademarks of Seagate T echnology, LLC. Cheetah, Sea FAX, SeaFONE, SeaBOARD, and SeaTDD are either trademarks or
registered trademar ks of Seagate Technology, LLC, or one of its subsidiar ies. All other trademarks or registered trademarks are the property of their respective owners.
No part of this publication may be reproduced in any form without written permission from
Seagate Technology, LLC.
Printed in the United States of America
Revision status summary sheet
Revision Date Writer/Engineer Sheets Affected
A 7/27/2000 L. Newman/G. Velaski 1/1, v thru viii, 1 thru 68.
B (Class A Release) 8/24/2000 L. Newman/G. Velaski Page 10.
C 8/29/2000 L. Newman/G. Velaski Pages 6, 9, 10, 38, 39, 40, 43, 45, 46, 49, 52,
57, and 58.
Cheetah 73FC Product Manual, Rev. C vii
Contents
1.0 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.0 Applicable standards and reference documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1 Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.1 Electromagnetic compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Reference documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.0 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1 Standard features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2 Media description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3 Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.4 Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.5 Unformatted and formatted capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.6 Programmable drive capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.7 Factory-installed accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.8 Factory-installed options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.9 User-installed accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.0 Performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.1 Internal drive characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.2 Seek performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.2.1 Access time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.2.2 Format command execution time for ≥ 512-byte sectors . . . . . . . . . . . . . . . . . . . . . 9
4.2.3 General performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.3 Start/stop time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.4 Prefetch/multi-segmented cache control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.5 Cache operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.5.1 Caching write data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.5.2 Prefetch operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.0 Reliability specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1 Error rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1.1 Environmental interference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1.2 Interface errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1.3 Write errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1.4 Seek errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.2 Reliability and service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.2.1 Mean time between failure (MTBF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.2.2 Field failure rate vs time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.2.3 Preventive maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2.4 Service life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2.5 Service philosophy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2.6 Service tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2.7 Hot plugging the drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2.8 S.M.A.R.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2.9 Drive Self Test (DST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.2.10 Product warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.0 Physical/electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.1 AC power requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.2 DC power requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.2.1 Conducted noise immunity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.2.2 Power sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.2.3 Current profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.3 Power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6.4 Environmental limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6.4.1 Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6.4.2 Relative humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
viii Cheetah 73FC Product Manual, Rev. C
6.4.3 Effective altitude (sea level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
6.4.4 Shock and vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
6.4.5 Air cleanliness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
6.4.6 Acoustics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
6.4.7 Electromagnetic susceptibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
6.5 Mechanical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
7.0 Defect and error management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.1 Drive internal defects/errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.2 Drive error recovery procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.3 FC-AL system errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
8.0 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
8.1 Drive ID/option selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
8.2 LED connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
8.2.1 J6 connector requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
8.3 Drive orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
8.4 Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
8.4.1 Air flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
8.5 Drive mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
8.6 Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
9.0 Interface requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
9.1 FC-AL features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
9.1.1 Fibre Channel link service frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
9.1.2 Fibre Channel task management functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
9.1.3 Fibre Channel task management responses . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
9.1.4 Fibre Channel port login . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
9.1.5 Fibre Channel port login accept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
9.1.6 Fibre Channel Process Login . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
9.1.7 Fibre Channel Process Login Accept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
9.1.8 Fibre Channel fabric login . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
9.1.9 Fibre Channel fabric accept login . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
9.1.10 Fibre Channel Arbitrated Loop options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
9.2 Dual port support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
9.3 SCSI commands supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
9.3.1 Inquiry data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
9.3.2 Mode Sense data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
9.4 Miscellaneous operating features and conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
9.5 FC-AL physical interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
9.5.1 Physical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
9.5.2 Connector requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
9.5.3 Electrical description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
9.5.4 Pin descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
9.5.5 FC-AL transmitters and receivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
9.5.6 Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
9.5.7 Fault LED Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
9.5.8 Active LED Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
9.5.9 Enable port bypass signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
9.5.10 Motor start controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
9.5.11 SEL_6 through SEL_0 ID lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
9.5.12 Device control codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
9.6 Signal characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
9.6.1 TTL input characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
9.6.2 LED driver signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
9.6.3 Differential PECL output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
9.6.4 Differential PECL input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
10.0 Seagate Technology support services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
Cheetah 73FC Product Manual, Rev. C ix
List of Figures
Figure 1. Cheetah 73FC family disc drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 2. Cheetah 73FC disc drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 3. Typical Cheetah 73FC drive +12V current profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 4. Typical Cheetah 73FC drive +5V current profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 5. DC current and power vs. input/output operations per second . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 6. Locations of PCBA components listed in Table 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Figure 7. Recommended mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 8. Mounting configuration dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Figure 9. Physical interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Figure 10. LED indicator connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 11. Air flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 12. Physical interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Figure 13. Port bypass circuit physical interconnect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Figure 14. FC-AL SCA device connector dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Figure 15. J6 connector dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Figure 16. FC-AL transmitters and receivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Figure 17. Transmit eye diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Figure 18. Receive eye diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Cheetah 73FC Product Manual, Rev. C 1
1.0 Scope
This manual describes Seagate® Cheetah 73FC (Fibre Channel) disc drives.
Cheetah 73FC drives suppor t the Fibre Channel A rbitrated Loop and SCSI Fibre Chan nel Protocol spec ifica-
tions to the extent described in this manual. The Fibre Channel Interface Manual (par t number 77767496)
describes the ge neral Fibre Chan nel Arbitrated Loop character istics of t his and othe r Seagate Fibre Channel
drives.
Figure 1.
Cheetah 73FC
family disc drive
2 Cheetah 73FC Product Manual, Rev. C
Cheetah 73FC Product Manual, Rev. C 3
2.0 Applicable standards and reference documentation
The drive has been developed as a system peripheral to the highest standards of design and construction. The
drive depends upon i ts host equip ment to provide adequ ate power and environment i n order to achieve optimum performance and compli ance with applicable industry and governm ental regulations. Special attention
must be given in the areas of safety, power distribution, shielding, audible noise control, and temperature regulation. In particular, the drive must be secur e ly mo unte d i n o rd er to guarantee the specified perfor ma nc e char acteristics. Mounting by bottom holes must meet the requirements of Section 8.5.
2.1 Standards
The Cheetah 73FC family complies with Seagate standards as noted in the appropriate sections of this manual
and the Seagate Fibre Channel Interface Manual, part number 77767496.
The Cheetah 73FC dis c drive is a UL recognized co mponent per UL1950, CSA certif ied to CAN/CSA C22.2
No. 950-95, and VDE certified to VDE 0805 and EN60950.
2.1.1 Electromagnetic compatibility
The drive, as delivered, is designed for system integration and installation into a suitable enclosure prior to use.
As such the drive is suppli ed as a subassembly and is not su bject to Subpar t B of Part 15 of the FCC Rules
and Regulations nor the Radio Interference Regulations of the Canadian Department of Communications.
The design characteristics of the drive serve to minimize radiation when installed in an enclosure that provides
reasonable shielding. As such, the drive is capable of meeting the Class B limits of the FCC Rules and Regulations of the Canadian Department of Communications when properly packaged. However, it is the user’s
responsibility to assure that the drive meets the appropriate EMI req uirements in their syst em. Shielded I/O
cables may be required if the e nclosure does not provide ad equate sh ielding. If the I/O c ables are externa l to
the enclosure, shielded cables should be used, with the shields grounded to the enclosure and to the host controller.
2.1.1.1 Electromagnetic susceptibility
As a component assembly, the drive is not required to meet any susceptibility per formance requ irements. It is
the responsibility of tho se integrating the dr ive within their sy stem s to perform thos e tests req uired and design
their system to ensu re that equipment operating in the sam e system as the drive or external to the s ystem
does not adversely affect the performance of the drive. See Section 5.1.1 and T able 1, DC power requirements.
Electromagnetic compliance
Seagate uses an indep endent laborator y to confir m compliance wi th the directives/standar ds for CE Marking
and C-Tick Marking. The drive was tested in a representative system for typical applications. The selected system represents the most popular characteristics for test platforms. The system configurations include:
• Typical current use microprocessor
• 3.5-inch floppy disc drive
• Keyboard
• Monitor/display
• Printer
• External modem
• Mouse
Although the test system with this Seagate model complies with the directives/standards, we cannot guarantee
that all systems will comply. The computer manufacturer or system i ntegrator shall confir m EMC complianc e
and provide the appropriate marking for their product.
Electromagnetic compliance for the European Union
If this model has the CE Marki ng it complies with the European Union requirem ents of the Electromagnetic
Compatibility Direc tive 89/336/EEC o f 03 May 1989 as ame nded by Direct ive 92/31/EE C of 28 Ap r il 1992 an d
Directive 93/68/EEC of 22 July 1993.
4 Cheetah 73FC Product Manual, Rev. C
Australian C-Tick
If this model has the C-Tick Markin g it complies with the Australia/New Zea land Standard A S/NZS3548 199 5
and meets the Electro magnetic Compatibility (EMC) Framework requirements of Australia’s Spectrum Management Agency (SMA).
2.2 Reference documents
Cheetah 73FC Installation Guide
Seagate part number: 83329483
Saftey and Regulatory Agency Specifications
Seagate part number: 75789512
Fibre Channel Interface Manual
Seagate part number: 77767496
ANSI Fibre Channel Documents
X3.230-1994 FC Physical and Signaling Interface (FC-PH)
X3.297.1997 FC-PH-2 Fibre Channel Physical and Signaling Interface-2
X3.303.1998 FC-PH-3 Fibre Channel Physical and Signaling Interface-3
X3.272-1996 FC Arbitrated Loop (FC-AL)
X3.269-1996 Fibre Channel Protocol for SCSI (FCP)
NCITIS TR-19 Private Loop SCSI Direct Attach
NCITIS TR-20 Fabric Loop Attachment (FC-FLA)
SFF-8045 Specification for 40-pin SCA-2 Connector with Parallel Selection.
SFF-8067 Specification for 40-pin SCA-2 Connector with Bidirectional Enclosure Services
Interface.
ANSI Small Computer System Interface (SCSI) Documents
X3.131-1994 (SCSI-2)
X3.270-199X6 (SCSI-3) Architecture Model
NCITS 305-199X (SCSI-3) Enclosure Services
30553-001 Specification for Acoustic Test Requirements and Procedures
In case of conflict between this document and any referenced document, this document takes precedence.
Cheetah 73FC Product Manual, Rev. C 5
3.0 General description
CheetahTM 73FC drives combine g iant magnetoresistive (GMR) head s, partial resp onse/maximum likelihood
(PRML) read channe l ele ctronics, embed ded ser vo techno logy, and a Fibre Cha nnel int erface to provide high
performance, high capa city data sto rage for a variety of systems inc luding engi neering wor kstatio ns, network
servers, mainframes, and supercomp uters.
Cheetah 73FC dr ives are random access s torage devices designed to suppor t the Fibre Channel Arbitrated
Loop (FC-AL) and SCSI Fibre Channe l Protocol as describe d in the ANSI specificatio ns, this document, and
the Fibre Channel Interface Manual (part number 77767496) which describes the general interface characteristics of this drive. Cheetah 73FC drives are classified as intelligent peripherals and provide level 2 conformance
(highest level) with the ANSI SCSI-1 standard.
The head and disc assembly (HDA) is environmentally sea led at the factory. Air recirculates within the HDA
through a non-replaceable filter to maintain a contamination-free HDA environment.
See Figure 2 for an exploded view of the drive. Never disassemble the HDA. This exploded view is for information only. Do not attempt to service items in the sealed enclosure (heads, media, actuator, etc.) as this requires
special facilities. The drive conta ins no parts replace able by the user and openin g the HDA for any reason
voids your warranty.
Figure 2. Cheetah 73FC disc drive
Cheetah 73FC drives use a dedicated landing zone at the innermost radius of the media to eliminate the possibility of destroying or degradi ng data by landing in the da ta zone. The heads automat ically go to the l anding
zone when power is removed from the drive.
An automatic shipping lock prevents potential damage to the heads and discs that results from movement during shipping and handl ing. The shipping lock disengages and the head lo ad process begins when power is
applied to the drive.
Cheetah 73FC drives decode track 0 location data from the servo data embedded on each surface to eliminate
mechanical transducer adjustments and related reliability concerns.
The drives also use a high-performance actuator assembly with a low-inertia, balanced, patented, straight arm
design that provides excellent performance with minimum power dissipation.
6 Cheetah 73FC Product Manual, Rev. C
3.1 Standard features
Cheetah 73FC
drives have the following standard features:
• Integrated dual port FC-AL controller
• Concurrent dual port transfers
• Support for FC arbitrated loop, private and public loop attachment
• Differential copper FC drivers and receivers
• Downloadable firmware using the FC-AL interface
• Supports SCSI enclosure services through the interface connector
• 128-deep task set (queue)
• Supports up to 32 initiators
• Drive selection ID and configuration options are set on the FC-AL backpanel or through interface com-
mands. Jumpers are not used on the drive.
• Fibre Channel worldwide name uniquely identifies the drive and each port
• User-selectable logical block size (512 to 704 bytes per logical block)
• Selectable frame sizes from 128 to 2,112 bytes
• Industry standard 3.5-inch half-high form factor dimensions
• Programmable logical block reallocation scheme
• Flawed logical block reallocation at format time
• Programmable auto write and read reallocation
• Reed-Solomon error correction code
• Sealed head and disc assembly (HDA)
• No preventive maintenance or adjustments required
• Dedicated head landing zone
• Automatic shipping lock
• Embedded Grey Code track address to eliminate seek errors
• Self-diagnostics performed at power on
• 1:1 interleave
• Zone bit recording (ZBR)
• Vertical, horizontal, or top down mounting
• Dynamic spindle brake
• 4,096 kbyte data buffer (16,384 kbytes on the FCV model). See Section 4.5.
• Embedded servo design
• Reallocation of defects on command (Post Format)
• Fibre Channel interface transports SCSI protocol
3.2 Media description
The media used on the dr ive has a di ameter of a pproximately 84 mm (approximate ly 3.3 inch es). The aluminum substrate is coate d with a thin film magnet ic material, overcoated wi th a proprietar y protective layer for
improved durability and environmental protection.
3.3 Performance
• Programmable multi-segmentable cache buffer
• 106 Mbytes/sec maximum instantaneous data transfers per port (212 Mbytes/sec with 2 GHz link rate)
• 10,025 RPM spindle; average latency = 2.99 msec
• Command queuing of up to 128 commands
• Background processing of queue
• Supports start and stop commands
• Adaptive seek velocity; improved seek performance
Cheetah 73FC Product Manual, Rev. C 7
3.4 Reliability
• 1,200,000 hour MTBF
• LSI circuitry
• Balanced low mass rotary voice coil actuator
• Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.)
• Dithering
3.5 Unformatted and formatted capacities
Formatted capacity de pends on the spare reall ocation sectors sche me select ed, the numbe r of dta tracks per
sparing zone, and the number of alternate sectors (LB As) per sparing zone. The following table shows the
standard OEM model capacity:
Formatted Unformatted
ST173404FC 087ACE4Dh (73.4) Gbytes 87.4 Gbytes
Standard OEM models are formatted to 512 bytes per block. You can order other capacities by requesting a different sparing scheme and logical block size.
The sector size is selectable at format time. Users having the necessary equipment may modify the data block
size before issuing a format command and obtain different formatted capacities than those listed. The
ST173404FC dr ives use a zone spar ing scheme. The drive is divided into frequency zones with a variable
number of spares in each zone.
Note.
For 2 gigabit operation sector sizes must be divisible by 8.
3.6 Programmable drive capacity
Using the Mode Select command, the drive can change its capacity to something less than maximum. See the
Mode Select (6) parame t er li s t ta ble in the Fibre Channel In ter face Manual, pa rt number 7776749 6. A value of
zero in the Number of Blocks field indica tes that the dr ive will not change the ca pacity it is curren tly formatted
to have. A number other than zero and less than the maximum number of LBAs in th e Number of Bl ocks field
changes the total dr ive capacity to the value in th e Number of Clo cks field . A value greater than the ma ximum
number of LBAs is rounded down to the maximum capacity.
3.7 Factory-installed accesso r ies
OEM standard dr ives are shipp ed with the Cheetah 7 3FC Insta llation Gui de (par t numb er 83329483) and the
Safety and Regulatory Agency Spec ifi catio ns page (part number 75789512).
3.8 Factory-installed options
You may order the following items which are incorporated at the m anufacturing facility durin g production or
packaged before shipping. Some of the options available are (not an exhaustive list of possible options):
• Other capacities can be ordered depending on sparing scheme and sector size requested.
• Single-unit shipping pack. The drive is nor mally shipped in bulk packaging to provide maxi mum protection
against transit damage. Units shipped individually require additional protection as provided by the single unit
shipping pack. Users planning single unit distribution should specify this option.
• The Cheetah 73FC Installation Guide, pa r t number 83 329483, is usu ally includ ed with each standard OE M
drive shipped, but extra copies may be ordered.
• The Safety and Regulat ory Agency Specifications, pa rt number 83329483, is usua lly included with each
standard OEM drive shipped, but extra copies may be ordered.
3.9 User-installed accessories
The following accessories are available. All kits may be installed in the field.
• Evaluation kit, part number 73473641.
This kit provides an adapte r car d (“T-card”) to allow cable conn ections for two FC ports and DC p ower. Two
twin axial cables, 6 feet in length, are included for the input and output connections to the FC interface.
• Single-unit shipping pack.
8 Cheetah 73FC Product Manual, Rev. C
Cheetah 73FC Product Manual, Rev. C 9
4.0 Performance characteristics
This section provides detailed information concerning performance-related characteristics and features of
Cheetah 73FC drives.
4.1 Internal drive characteristics
ST173404FC
Drive capacity 73.4 ..........................Gbytes (formatted, rounded off value)
Read/write data heads 24
Bytes per track 215-248....................KBytes (average, rounded off values)
Bytes per surface 3,035 ........................Mbytes (unformatted, rounded off value)
Tracks per surface 14,100 ......................Tracks (user accessible)
Tracks per inch 18,145 ......................TPI
Peak bits per inch 334 ...........................kBPI
Internal data rate 280-427....................Mbits/sec (variable with zone)
Disc rotation speed 10,025 ......................rpm (+
Avg rotational latency 2.99 ..........................msec
4.2 Seek performance characteristics
4.2.1 Access time
Including contr oller overhead (w ithout
disconnect)
1, 2
(msec)
0.5%)
Not including controller overhead
(without disconnect)
1,2
(msec)
Read Write Read Write
Average Typical
Single track Typical
Full stroke Typical
3,4
3,4
3,4
6.05 6.55 5.85 6.35
0.8 1.1 0.6 0.9
14.2 15.2 14.0 15.0
1. Execution time measured from receipt of the command to the FCP Response.
2. Assumes no errors and no sector has been relocated.
3. Typical access times are measured under nominal conditions of temperature, voltage, and horizontal orientation as
measured on a representative sample of drives.
4. Access time = controller overhead + average seek time.
Access to data = controller overhead + average seek time + latency time.
4.2.2 Format command execution time for ≥ 512-byte sectors
ST173404FC
Maximum (with verify) 240 minutes
Maximum (without verify) 120 minutes
10 Cheetah 73FC Product Manual, Rev. C
4.2.3 General performance characteristics
Minimum sector interleave 1 to 1
Data buffer to/from disc media (one 512-byte logical block)*
Minimum 26.7 MBytes/sec
Average 33.0 MBytes/sec
Maximum 40.2 MBytes/sec
Fibre Channel Interface maximum instantaneous transfer rate 1 GHz
106 Mbytes/se c*p er
port (dual port = 212
Mbytes/sec*)
Logical block sizes
Default is 512-byte data blocks
Variable 512 to 704 bytes per sector in even number of bytes per sector.
If n (number of bytes per sector) is odd, then n-1 will be used.
Read/write consecutive sectors on a track
Flaw reallocation performance impact (for flaws reallocated at format time
using the spare sectors per sparing zone reallocation scheme.)
Average rotational latency
*Assumes no errors and no reloc ated l ogica l b loc ks . Rate meas ured from the sta rt of the first logic al
block transfer to or from the host.
Yes
Negligible
2.99 msec
2 GHz
212 Mbytes/sec*per
port (dual port = 424
Mbytes/sec*)
4.3 Start/stop time
If the Motor Start option is disabled, the drive becomes ready within 30 seconds after DC power is applied. If a
recoverable error condition is detected during the start sequence, the drive executes a recovery procedure and
the time to become ready may exceed 30 seconds. Stop time is less than 30 seconds (maximum) from removal
of DC power.
If the Motor Star t option is enabled, the i nternal contr oller accepts th e commands list ed in the Fibre Channel
Interface Manual less than 3 seconds after DC power has been applied. After the Moto r Start co mmand has
been received, the drive becomes ready for normal operations within 30 seconds (excluding the error recovery
procedure). The Motor Start command can also be used to command the drive to stop the spindle.
There is no power control switch on the drive.
4.4 Prefetch/multi-segmented cache control
The drive provides a prefetch (read look-ahead) and multi-segmented cache con trol algorithms that in many
cases can enhance s ystem performance. Cache refers to the drive buffer storage space when it is used in
cache operations. To select this feature, the host sends the Mode Select command with the pro per values in
the applicable bytes in page 08h. Prefetch and cache operations are indep end ent features from the sta ndp oin t
that each is en abled and disabled ind ependently us ing the Mode Select comm and; however, in actual operation, the prefetch feature overlaps cache operation somewhat as described in sections 4.5.1 and 4.5.2.
All default cache and prefetch mode pa rameter values (Mode Page 08h) for standard OEM versions of this
drive family are given in Table 16.
Cheetah 73FC Product Manual, Rev. C 11
4.5 Cache operation
Note.
Of the 4,096 kbytes physical buffer space i n the drive, 3,600 kbytes (14,399 k bytes of the 16,384 kbytes on
FCV units) can be used as a cache.
The buffer can be divided into logical segments (using Mode Select Page 08h, byte 13) from which data is read
and to which data is written.
The drive keeps track of the logical block addresses of the data stored in each segment of the buffer. If the
cache is enabled (see RCD bit in the Fibr e Ch ann el I nter face Manual), d ata re ques te d by the h ost with a r ea d
command is retr ieved from the buffer, if possible, before any disc access is initia ted. If ca che operation is not
enabled, the buffer (still segmented with the required number of segm ents) is still used, but only a s circular
buffer segments during disc medium read operations (disregarding Prefetch operation for the moment). That is,
the drive does not check in the buffer segments for the requested read data, but goes directly to the medium to
retrieve it. The retrieved data merely passes thr ou gh some buffer segment on the way to the host. On a ca ch e
miss, all data transfers to the host are in accordance with buffer-full ratio rules. On a cache hit, the drive ignores
the buffer-full ratio rules. See the explanation provided with the information about Mode Page 02h (disconnect/
reconnect control) in the Fibre Channel Interface Manual.
The following is a simplified description of the prefetch/cache operation:
Case A
1. Drive transfers to the initiator the first logical block requested plus all subsequent contiguous logical blocks
2. When a requested logica l block is reached that is not in any cache seg ment, the drive fetches it and any
3. If the prefetch feature is enabled, refer to section 4.5.2 for operation from this point.
Refer to the Fibre Channel Interface Manual for more detail concerning the cache bits.
—read command is received and the first logical block is already in the cache:
that are already in the cache. This data may be in multiple segments.
remaining requested logical block addresses fr om the disc and pu ts them in a se gment of the ca che. The
drive transfers the remaining requested log ical blocks from the cache to the host in accordance with the
Mode Select Disconnect/Reconnect parameters, page 02h.
Case B
1. The drive fetches the requested logic al blocks from the disc and transfers them into a segment, and the n
2. If the prefetch feature is enabled, refer to section 4.5.2 for operation from this point.
During a prefetch, the drive crosses a cylinde r boundary to fetch data only if the Discontinuit y (DISC) bi t is set
to 1 in bit 4 of byte 2 of the Mode Select parameters page 08h. Default is zero for bit 4.
Each cache segment is actually a self-contained circ ular buffer whose length is an integer number of logical
blocks. The wrap-around capability of the individual segments greatly enhances the cache’s overall performance, allowing a wide range of user-selectable configu rations. The drive supports operation of any inte ger
number of segments fro m 1 to 16. Di vide the 3,60 0 kbytes (14 ,399 kbytes on the FCF model ) in the buffer by
the number of segments to get the segment size. Default is 3 segments.
Note.
4.5.1 Caching write data
Write caching is a wr ite op eration by the dr ive that makes use of a drive buffer storage area where the data t o
be written to the medium is stored whil e the drive p erforms the Write command.
If read caching is enabled (RCD=0), then data written to the medium is retained in the cache to be made available for future read cache hits. The s ame buffer space and segme ntat ion is u sed a s set up for read func tions.
The buffer segmentation scheme is set up or changed independently, having nothing to do with the state of
RCD . When a write command is issued, if RCD=0, the cache is first checked to see if any logical blocks that are
—A Read command requests data, and the first logical block is not in any segment of the cache:
from there to the host in accordance with the Mode Select Disconnect/Reconnect parameters, page 02h.
The size of each segment is not repo r ted by Mode Sense c ommand pa ge 08h, bytes 14 and 15. The
value 0XFFFF is always reported regardless of the actual size of the segment. Sending a size specification using the Mode Selec t co mmand (bytes 14 a nd 15) does not set up a new seg ment s ize. If the
STRICT bit in Mode page 00h (byte 2, bit 1) is set to one, the drive responds as it does for any attempt
to change an unchangeable parameter.
12 Cheetah 73FC Product Manual, Rev. C
to be written are already sto red in the cache from a previous read or wr ite command. If there are, the respective cache segments are cleared. The new data is cached for subsequent Read commands.
If the number of write data logical blocks exceed the size of the segment being written into, when the end of the
segment is reached, the data is written into the beginning of the same cache segment, overwriting the data that
was written there at the begin nin g of the operat ion ; however, the drive does not overwrite data that has not yet
been written to the medium.
If write caching is enabled (WCE=1), then the drive may return Good status on a write command after the data
has been transferred into the cache, but before the data has been written to the medium. If an error occurs
while writing the data to the medium, and Good status has already been returned, a deferred error will be generated.
The Synchronize Cache command may be used to force the drive to write all cached write data to the medium.
Upon completion of a Synchronize Cache command, all data received from previous write commands will have
been written to the medium.
Table 16 shows the mode default settings for the drive.
4.5.2 Prefetch operation
If the Prefetch feature is enabled, data in conti guous lo gical blocks on the disc i mmedia tely b eyond that which
was requested by a Read command are retrieved and stored in the buffer for immediate transfer from the buffer
to the host on subsequent Rea d comma nds tha t request th ose log ical blocks (this is tr ue even if cache operation is disabled). Though the pr efetch operation uses the buffer as a cache, finding the reques ted data in the
buffer is a prefetch hit, not a cache operation hit.
To enable Prefetch, us e Mode Select page 08h, byte 12, bit 5 (Disable Read Ahea d - DRA bit). DRA bit = 0
enables prefetch.
Since data that is prefetched replaces data already in som e buffer segments, the host can limit the amoun t of
prefetch data to optimize system performanc e. The Max Prefetch field (bytes 8 and 9) limits the amount of
prefetch. The drive does not use the Prefetch Ceiling field (bytes 10 and 11).
During a prefetch operation, the drive cross es a cy linder bou nda ry to fetch more data only if Mode paramete rs
page 08h, byte 2, bit 4 is set to 1 (Discontinuity--DISC bit).
When prefetch (read look-ahe ad) is enabled (enabled by DRA = 0), it operates under the control of ARLA
(Adaptive Read Look-Ahead). If the host uses software interleave, ARLA enables prefetch of contiguous blocks
from the disc when it sense s that a prefetch hit will l ikely occur, even if two consecutive read operations were
not for physically contiguous blocks of data (e.g. “software interleave”). ARLA disables prefetch when it decides
that a prefetch hit will not likely occur. If the host is not using softwa re interleave, and if two sequential read
operations are not for contiguous blocks of data , ARL A dis ables pre fetch, but as long as s equ enti al read oper ations request contiguous blocks of data, ARLA keeps prefetch enabled.
Cheetah 73FC Product Manual, Rev. C 13
5.0 Reliability specifications
The following reliability speci fications assume correc t host and drive operational in terface, including all interface timings, power supply voltages, and environmental requirements.
Seek error rate:
Read Error Rates
1
Recovered Data
Unrecovered media data:
Miscorrected media data:
Interface error rate:
Less than 10 errors in 10
Less than 10 errors in 10
Less than 1 sector in 10
Less than 1 sector in 10
Less than 1 error in 10
Less than 1 error in 10
See Section 9.6.4, "Differential PECL input." on page 58
MTBF: 1,200,000 hours
Service life: 5 years
Preventive maintenance: None required
1. Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated.
5.1 Error rates
The error rates stated in this manual assume the following:
• The drive is operated in accordanc e with this manual using DC power as d efined in paragraph 6.2, "DC
power requirements."
• The drive has been formatted with the FC-AL Format command.
• Errors caused by media defects or host system failures are excluded from error rate computations.
• Assume random data.
8
seeks
12
bits transferred (OEM default settings)
15
bits transferred
21
bits transferred
12
bits transferred with minimum receive eye.
14
bits transferred with typical receive eye.
5.1.1 Environmental interference
When evaluating systems operation under conditio ns of electromagnetic int erference (EMI), the performance
of the drive within the system is consid ered ac ceptable if t he dri ve does not gene rate an unrec overable condition.
An unrecoverable error, or condition, is defined as one that:
• is not detected and corrected by the drive itself
• is not detected from the error or fault status provided through the drive or FC-AL interface
• is not recovered by normal drive or system recovery procedures without operator intervention
5.1.2 Interface errors
An interface error is defin ed as a failure of the receiver on a por t to recover the data as transmitted by the
device port connected to the receiver. The error may be detected as a running disparity error, illegal code, loss
of word sync, or CRC error. The total error rate for a loop of devices is the sum of the indi vidual device error
rates.
5.1.3 Write errors
Write errors can occur as a result of media defects, environmental interference, or equipment malfunction.
Therefore, write errors are not predictable as a function of the number of bits passed.
If an unrecoverable write error occurs beca use of a n equipm ent mal functi on in the dr ive, the error is classi fied
as a failure affecting MTBF. Unrecoverable write errors are thos e that ca nnot be cor rected wi thin two attem pts
at writing the record with a read verify after each attempt (excluding media defects).
14 Cheetah 73FC Product Manual, Rev. C
5.1.4 Seek errors
A seek error is defined as a failure of the drive to posit ion the he ads to the a ddressed track. If the error recovery fails, a seek positioning error (15h) is reported with a Medium (03h) or Hardware Error (04h) reported in the
sense key. Thi s is an u nrecoverable seek error. Unrecoverable seek errors are classified a s failures for MTBF
calculations. Refer to the Fibre Channel Interface Manual, part number 77767496, for Request Sense information.
5.2 Reliability and service
You can enhance the reliability of Cheetah 73FC disc drives by ensuring that the drive receives adequate cooling. Section 6.0 provide s recommended air- flow information, temperatur e measurements, and other information, which you can use to enhance the service life of the drive.
5.2.1 Mean 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 spec ified in Sectio n 6.4.1 are not exceeded. Shor t-ter m excursions up to the
specification limits of th e op erati ng e nvironmen t wi ll not a ffect MTBF p er formanc e. Ope rating th e 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 oper ating 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 servic e. Each disc dr ive must have accumulated at least ni ne months of op eration. Data is c alculated 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. p redi ctive failure indicates th at the d r ive is deter iora ting to an imm inent failure and is consi dere d
an MTBF hit.
5.2.2 Field failure rate vs time
The expected field failure rate is listed below. Drive utilization will vary. An estimate range of utilization is:
• 720 power-on hours (POH) per month
• 250 on/off cycles per year
• System provides adequate cooling to ensure the case temperatures specified in Section 6.4.1 are not
exceeded.
Month Parts per million (PPM)
1 2,500
2 1,600
3 1,200
4 1,000
5890
6840
7805
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