Seagate ST9160511NS manual Acoustics, Electromagnetic immunity, Radio frequency environments

3.10Acoustics

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 3:	Fluid Dynamic Bearing (FDB) motor acoustics
		Active	Idle*
ST9500530NS		2.6 bels (typ)	2.3 bels (typ)
ST9160511NS		2.5 bels (typ)	2.1 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.

3.11Electromagnetic immunity

When properly installed in a representative host system, the drive operates without errors or degradation in performance when subjected to the radio frequency (RF) environments defined in the following table:

Table 4:	Radio frequency environments
Test		Description	Performance level	Reference standard
Electrostatic		Contact, HCP, VCP: ± 4 kV; Air: ± 8 kV	B	EN 61000-4-2: 95
discharge
Radiated RF		80 to 1,000 MHz, 3 V/m,	A	EN 61000-4-3: 96
immunity		80% AM with 1 kHz sine		ENV 50204: 95
		900 MHz, 3 V/m, 50% pulse modulation @ 200 Hz
Electrical fast		± 1 kV on AC mains, ± 0.5 kV on external I/O	B	EN 61000-4-4: 95
transient
Surge immunity		± 1 kV differential, ± 2 kV common, AC mains	B	EN 61000-4-5: 95
Conducted RF		150 kHz to 80 MHz, 3 Vrms, 80% AM with 1 kHz sine	A	EN 61000-4-6: 97
immunity
Voltage dips,		0% open, 5 seconds	C	EN 61000-4-11: 94
interrupts		0% short, 5 seconds	C
		40%, 0.10 seconds	C
		70%, 0.01 seconds	B

Constellation Serial ATA Product Manual, Rev. D 17