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Figure 3, St3146855lc dc current and power vs. iops (lvd) – Seagate CHEETAH 15K.5 SCSI ST3146855LC User Manual

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Cheetah 15K.5 SCSI Product Manual, Rev. J

27

ST3146855LW/ST3146855LC

For drives using low voltage differential interface circuits, typical power dissipation under idle conditions is
10.39

watts (35.45

BTUs per hour).

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. ST3146855LC DC current and power vs. IOPS (LVD)

ST3146855LC CURRENT/POWER vs THROUGHPUT (SCSI - LVD)

Random 8 Block Reads

0.000

0.200

0.400

0.600

0.800

1.000

1.200

1.400

1.600

1.800

0.0

50.0

100.0

150.0

200.0

250.0

300.0

350.0

400.0

I/Os per Second

Ampe

re

s

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

Power (watts)

5Vo lt A

12 Vo lt A

Watts