Fujitsu MPG3204AH-E, Product Manual

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C141-E116-01EN 1 - 10
(4) Service life
In situations where management and handling are correct, the disk drive requires no overhaul for
five years when the DE surface temperature is less than 48°C. When the DE surface temperature
exceeds 48°C, the disk drives requires no overhaul for five years or 20,000 hours of operation,
whichever occurs first. Refer to item (3) in Subsection 3.3 for the measurement point of the DE
surface temperature.
(5) Data assurance in the event of power failure
Except for the data block being written to, the data on the disk media is assured in the event of any
power supply abnormalities. This does not include power supply abnormalities during disk media
initialization (formatting) or processing of defects (alternative block assignment).
1.8 Error Rate
Known defects, for which alternative blocks can be assigned, are not included in the error rate
count below. It is assumed that the data blocks to be accessed are evenly distributed on the disk
media.
(1) Unrecoverable read error
Read errors that cannot be recovered by read retries without user's retry and ECC corrections shall
occur no more than 10 times when reading data of 10
15
bits. Read retries are executed according to
the disk drive's error recovery procedure, and include read retries accompanying head offset
operations.
(2) Positioning error
Positioning (seek) errors that can be recovered by one retry shall occur no more than 10 times in
10
7
seek operations.
1.9 Media Defects
Defective sectors are replaced with alternates when the disk is formatted prior to shipment from the
factory (low level format). Thus, the host sees a defect-free device.
Alternate sectors are automatically accessed by the disk drive. The user need not be concerned
with access to alternate sectors.
Chapter 6 describes the low level format at shipping.