Seagate ST91000641SS ユーザーズマニュアル

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Constellation.2 SAS Product Manual, Rev. H
33
7.5
Environmental limits
Temperature and humidity values experienced by the drive must be such that condensation does not occur on 
any drive part. Altitude and atmospheric pressure specifications are referenced to a standard day at 58.7°F 
(14.8°C). Maximum wet bulb temperature is 82°F (28°C).
7.5.1
Temperature
a. Operating
The drive meets the operating specifications over a 41°F to 140°F (5°C to 60°C) drive case temperature 
range with a maximum temperature gradient of 36°F (20°C) per hour.
The maximum allowable drive case temperature is 60°C. See Figure 7 for HDA case temperature measure-
ment location
The MTBF specification for the drive assumes the operating environment is designed to maintain nominal 
case temperature. The rated MTBF is based upon a sustained case temperature of 104°F (40°C).  Occa-
sional excursions in operating temperature between the rated MTBF temperature and the maximum drive 
operating case temperature may occur without impact to the rated MTBF temperature.  However continual 
or sustained operation at case temperatures beyond the rated MTBF temperature will degrade the drive 
MTBF and reduce product reliability.
Air flow may be required to achieve consistent nominal case temperature values (see Section 11.2). To con-
firm that the required cooling is provided for the electronics and HDA, place the drive in its final mechanical 
configuration, and perform random write/read operations. After the temperatures stabilize, measure the 
case temperature of the drive.
b. Non-operating
–40° to 158°F (–40° to 70°C) package ambient with a maximum gradient of 36°F (20°C) per hour. This 
specification assumes that the drive is packaged in the shipping container designed by Seagate for use with 
drive.  
HDA Temp.
Check Point
    
Figure 7. 
Location of the HDA temperature check point
Note.
Image is for reference only, may not represent actual drive.
7.5.2
Relative humidity
The values below assume that no condensation on the drive occurs.
a. Operating
5% to 95% non-condensing relative humidity with a maximum gradient of 20% per hour.
b. Non-operating
5% to 95% non-condensing relative humidity.