Fujitsu MAW3073NC, Product/Maintenance Manual

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C141-E226 2-5
(*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 10 per
10
16
bits read.
CAUTION
Data loss
The drive adopts Reed-Solomon code for ECC. The sector-data is
divided into 3 interleaving sectors, and ECC is performed in each
sector where the maximum number of errors (up to 9 byte) can be
corrected. [Total maximum byte: 9 byte
×
3 ( interleave) = 27 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 HDD during its lifetime is 1,200,000 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
Failure of the equipment means failure that requires repair, adjustments, or replacement.
Mishandling by the operator, failures due to bad environmental conditions, power trouble, host
system trouble, cable failures, or other failures not caused by the equipment are not considered.