Seagate Cheetah ST3146854, User Manual

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34 Cheetah 15K.4 SCSI Product Manual, Rev. D
6.4 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).
6.4.1 Temperature
a. Operating
The maximum allowable continuous or sustained HDA case temperature for the rated MTBF is 122°F
(50°C) The maximum allowable HDA case temperature is 60°C. Occasional excursions of HDA case tem-
peratures above 122°F (50°C) or below 41°F (5°C) may occur without impact to specified MTBF. Continual
or sustained operation at HDA case temperatures outside these limits may degrade MTBF.
Provided the HDA case temperatures limits are met, the drive meets all specifications over a 41°F to 131°F
(5°C to 55°C) drive ambient temperature range with a maximum temperature gradient of 36°F (20°C) per
hour. Air flow may be needed in the drive enclosure to keep within this range (see Section 8.3). Operation at
HDA case temperatures outside this range may adversely affect the drives ability to meet specifications. To
confirm that the required cooling for the electronics and HDA case is provided, place the drive in its final
mechanical configuration, perform random write/read operations and measure the HDA case temperature
after it has stabilized.
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.
Figure 14. Locations of the HDA temperature check point
6.4.2 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.
6.4.3 Effective altitude (sea level)
a. Operating
–1,000 to +10,000 feet (–305 to +3,048 meters)
b. Non-operating
–1,000 to +40,000 feet (–305 to +12,210 meters)
HDA Temp.
Check Point .5"
1.0"