30 Constellation ES Series SAS Product Manual, Rev. F

7.4 Power dissipation

2TB models in 3Gb operation
Please refer to Table 2 for power dissipation numbers.
To obtain operating power for typical random read operations, refer to the following I/O rate curve (see Figure
4). Locate the typical I/O rate for a drive in your system on the horizontal axis and read the corresponding +5
volt current, +12 volt current, and total watts on the vertical axis. To calculate BTUs per hour, multiply watts by
3.4123.
Figure 4. 2TB models (3Gb) DC current and power vs. input/output operations per second
Note. For power details about SED vs. non-SED drive, please refer to section 7.8.
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0.9
1.0
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I/Os per Second

ST32000444SS CU RRENT / PO WE R vs T HRO UGHP UT (S A S - 3.0GB)

Random 8 Block Reads

5Volt A
12 Vol t A
Watts