Fujitsu MAS3184NC - Enterprise 18.4 GB Hard Drive, Product/Maintenance Manual

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C141-E185 2-5
(*4)
At power-off state after installation
Vibration displacement should be less than 2.5 mm.
(*5)
Input voltages are specified at the drive connector side, during drive ready state.
(*6)
The terminator power pin (SCSI connector) which supplies power to other terminators is not used
(See Section 4.3).
(*7)
High frequency noise (over 20 MHz) is less than 100 mVp-p.
2.1.4 Error rate
Errors detected during initialization and replaced by alternate block assignments are not included
in the error rate. Data blocks to be accessed should be distributed over the disk medium equally.
(1) Unrecoverable error rate
Errors which cannot be recovered within 63 retries and ECC correction should not exceed 1 per
10
15
bits.
CAUTION
Data loss
For MAS series, Reed Solomon codes are applied for their ECC.
The sector-data is divided into 4 interleaving sectors, and ECC is
performed in each sector where the maximum number of errors
(up to 5 byte) can be corrected. [Total maximum byte: 5 byte
×
4
( interleave) = 20 byte]
If the error of read sector keeps allowable error byte number,
correction is performed. However, if error byte exceeds its
allowable number, correction may not be performed properly.
(2) Positioning error rate
Positioning errors which can be recovered by one retry should be 10 or less per 10
8
seeks.
2.1.5 Reliability
(1) Mean Time Between Failures (MTBF)
MTBF of the IDD during its life time is 1,2000,000 hours (operating: 24 hours/day, 7 days/week
average DE surface temperature: 50°C or less).
Note:
The MTBF is defined as:
Operating time (hours) at all field sites
MTBF=
The number of equipment failures from all field sites