32 Constellation ES Series SAS Product Manual, Rev. F

1TB 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

6). 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 6. 1TB 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.
0
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0 20 40 60 80 100 120 140 160
P
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I/Os per S e cond

ST31000424SS CU RRE NT /PO W ER vs T HR OUG HP UT (SAS - 3.0GB)

Random 8 Blo c k Reads

5Volt A
12 Volt A
Watts