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

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2-6 C141-E185
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.
(2) Mean Time to Repair (MTTR)
MTTR is the average time taken by a well-trained service mechanic to diagnose and repair a drive
malfunction. The drive is designed for a MTTR of 30 minutes or less.
(3) Service life
The service life under suitable conditions and treatment is as follows.
The service life is depending on the environment temperature. Therefore, the user must design the
system cabinet so that the average DE surface temperature is as possible as low.
•
DE surface temperature: 40°C or less 5 years
•
DE surface temperature: 41°C to 45°C 4.5 years
•
DE surface temperature: 46°C to 50°C 4 years
•
DE surface temperature: 51°C to 55°C 3.5 years
•
DE surface temperature: 56°C to 60°C 3 years
•
DE surface temperature: 61°C and more Strengthen cooling power so that DE surface
temperature is 60°C or less.
Even if the IDD is used intermittently, the longest service life is 5 years.
Note:
The "average DE surface temperature" means the average temperature at the DE surface
throughout the year when the IDD is operating.
(4) Data security at power failure
Integrity of the data on the disk is guaranteed against all forms of DC power failure except on
blocks where a write operation is being performed. The above does not applied to formatting
disks or assigning alternate blocks.