Toshiba MK4006GAH Manuale Utente

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Toshiba Corporation Digital Media Network Company 
 
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    © 2003, Copyright TOSHIBA Corporation All Rights Reserved 
 
10. RELIABILITY 
A failure is defined as an inability of the drive to perform its specified function described in the requirements 
of this document when being operated under the normal conditions or conditions specified in this document. 
However , damages caused by operation mistake, mishandling, accidents, system errors and other 
damages that can be induced by the customers are not defined as failure.   
10.1 Error Rate 
10.1.1 Non- Recoverable Error Rate 
1 error per 10
13 
bits read 
 
The defective sectors allocated to the spare locations in the factory are not counted in the error rate. 
10.1.2  Seek Error Rate 
1 error per 10
6
 seeks 
 
A seek error is a positioning error recoverable by a retry including recalibration. 
10.2  Mean Time to Failure (MTTF) 
A failure means that the drive can not execute the function defined in this document under the nominal 
temperature, humidity and the other conditions specified in this document . Damages caused by operation 
mistake, mishandling,    system failure and other damages occurred under the conditions which are not 
described in this document are not considered as the failure. 
MTTF  
 300,000 hours 
Conditions  
       Power on hours      
 2,800 hours ( 200 days x 14 hours ) / year) 
       Operating hours     
 600 hours ( 200 days x  3 hours ) / year) 
       Seek hours          
 1.30 x 10
6
 seeks / month 
       Number of load / unload   
 70 times / hour  ( 60,000 times / year ) 
              Environment                 
 Normal  ( 25oC, 101.3 kPa    ( 1,013 mb ) )       
 
10.3 Product Life 
5 years or 20,000 power on hours whichever comes earlier 
10.4 Repair 
A defective drive should be replaced. Parts and subassemblies should not be repaired individually . 
10.5  Preventive Maintenance (PM) 
No preventive maintenance is required.