Seagate ST91000640NS ユーザーズマニュアル

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Constellation.2 Serial ATA Product Manual, Rev. B
19
3.9.5
Vibration
All vibration specifications assume that the drive is mounted securely with the input vibration applied at the 
drive mounting screws. Vibration may be applied in the X, Y or Z axis.
3.9.5.1
Operating vibration
The maximum vibration levels that the drive may experience while meeting the performance standards speci-
fied in this document are specified below.
3.9.5.2
Nonoperating vibration
The maximum nonoperating vibration levels that the drive may experience without incurring physical damage 
or degradation in performance when subsequently put into operation are specified below.
3.10
Acoustics
Drive acoustics are measured as overall A-weighted acoustic sound power levels (no pure tones). All mea-
surements are consistent with ISO document 7779. Sound power measurements are taken under essentially 
free-field conditions over a reflecting plane. For all tests, the drive is oriented with the cover facing upward.
Note. For seek mode tests, the drive is placed in seek mode only. The number of seeks per second is defined 
by the following equation: 
 
 
(Number of seeks per second = 0.4 / (average latency + average access time)
Table 3: 
Fluid Dynamic Bearing (FDB) motor acoustics
Active
Idle*
2.8 bels (typ)
2.2 bels (typ)
*During periods of drive idle, some offline activity may occur according to the S.M.A.R.T. specification, which may increase acoustic and 
power to operational levels.
5–500 Hz
0.50 Gs
5–500 Hz
3.0 Gs