Seagate ST31230DC, Руководство по эксплуатации продукта

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20 Product Manual - Hawk 2LP Family (Wide) SCSI-2 (Volume 1), Rev. A
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7.3 Heat/power dissipation
For drives with single ended interface circuits, typical operating random read power dissipation is 9.0 watts
(30.8 BTUs per hour) of DC power average at nominal voltages. Typical power dissipation under idle conditions
is 6.0 watts (20.5 BTUs per hour).
For drives with differential interface circuits, typical operating random read power dissipation is 9.5 watts (32.5
BTUs per hour) of DC power average at nominal voltages. Typical power dissipation under idle conditions is
6.75 watts (23.1 BTUs per hour).
7.4 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).
7.4.1 Temperature
a. Operating
The drive meets all specifications over a 41°F to 131°F (5°C to 55°C) drive ambient temperature range with
a maximum gradient of 36°F (20°C) per hour. The enclosure for the drive should be designed such that
the temperatures at the locations specified in Table 7.4.1-1, column 1 are not exceeded. Air flow may be
needed to achieve these temperature values. Operation at case temperatures above these values may
adversely affect the drives ability to meet specifications.
The MTBF specification for the drive is based on operating at an ambient temperature of 95°F (35°C).
Occasional excursions to drive ambient temperatures of 55°C or 5°C may occur without impact to specified
MTBF. To achieve the specified MTBF, the values of Table 7.4.1-1 Column 2 must be considered
maximum average operating case temperatures. Air flow may be needed to achieve these temperatures.
Continual or sustained operation at case temperatures above these values may degrade MTBF.
Table 7.4.1-1. PCB and HDA temperatures
Items Column 1 Column 2
in Maximum Case Typical Case
Figure Temperatures (°C) Temperatures (°C)
7.4.1-1 Operating (55° Ambient)[2] at 35°C Ambient[1]
HDA 65 45
U2 88 68
U31 100 59
U17 101 60
U5 98 58
U3 91 54
Note.
[1] The temperatgures shown in Column 2 were measured on an unmounted drive lying on its side during
random write/reads at 100% duty cycle in still air.
[2] The temperatures shown in Column 1 are calculated and may not reflect actual operating values. Sufficient
cooling air may be required to ensure that these values are not exceeded.
b. Non-Operating
-40° to 158°F (-40° to 70°C) package ambient with a maximum gradient of 45°F (25°C) per hour. This
specification assumes that the drive is packaged in the shipping container designed by Seagate for use
with drive.