Fujitsu MHY2160BS 用户手册

 

(1)  Mean time between failures (MTBF)  

 

Conditions of 500,000 h 

Power-on time  24H/day or less 

 

Operating time  50 % or less of power-on time 

 Temperature 

 

Humidity 

5 to 45 

°C (Disk Enclosure surface)

8 to 90 % (ambient) 
But humidity bulb temperature  
29 

°C or less 

 

Conditions of 300,000 h 

Power-on time  24H/day or less 

 

Operating time  50 % or less of power-on time 

 Temperature 

 

Humidity 

5 to 60 

°C (Disk Enclosure surface)

8 to 90 % (ambient) 
But humidity bulb temperature 29 

°C 

or less 

MTBF is defined as follows: 

 

Total operation time in all fields 

MTBF= (H) 

 

number of device failure in all fields (*1) 

*1  "Disk drive defects" refers to defects that involve repair, readjustment, or 

replacement.  Disk drive defects do not include failures caused by external factors, 
such as damage caused by handling, inappropriate operating environments, defects 
in the power supply host system, or interface cable. 

(2)  Mean time to repair (MTTR)  

The mean time to repair (MTTR) is 30 minutes or less, if repaired by a specialist 
maintenance staff member. 

(3) Service life 

In situations where management and handling are correct, the disk drive requires 
no overhaul for five years or 30,000 hours of operation, whichever occurs first, 
when the DE surface temperature is less than 45 

°C.  When the DE surface 

temperature exceeds 45 

°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 3.2 for the measurement point of the DE surface 
temperature.  The operating conditions of Service life are based on the equal 
conditions with MTBF. 

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