Seagate ST3160211AS, ST380211AS Acoustics, Vibration, Operating vibration, Nonoperating vibration

2.9.6Vibration

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.

2.9.6.1Operating vibration

The maximum vibration levels that the drive may experience while meeting the performance standards speci- fied in this document are specified below.

5–22 Hz	0.25	Gs (Limited displacement)
23–350 Hz	0.50 Gs
350–500 Hz	0.25	Gs

2.9.6.2Nonoperating 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.

5–22 Hz	0.25 Gs (limited displacement)
23–350 Hz	5.0 Gs
350–500 Hz	1.0 Gs

2.10Acoustics

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 5:	Fluid Dynamic Bearing (FDB) motor acoustics
		Idle*	Seek
All models		2.7 bels (typ)	2.9 bels (typ)
		2.8 bels (max)	3.1 bels (max)

*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.

Barracuda 7200.9 Serial ATA Product Manual, Rev. C 17