Seagate ST1000NM0031, ST2000NM0031, 100650923 Acoustics, Fluid Dynamic Bearing FDB motor acoustics

2.10ACOUSTICS

Drive acoustics are measured as overall A-weighted acoustic sound power levels (no pure tones). All measurements 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 equa- tion:

(Number of seeks per second = 0.4 / (average latency + average access time)

Table 6 Fluid Dynamic Bearing (FDB) motor acoustics

	Idle*	Performance seek
2TB models	2.7 bels (typ)	3.0 bels (typ)
	2.9 bels (max)	3.3 bels (max)
1TB models	2.2 bels (typ)	2.8 bels (typ)
	2.5 bels (max)	3.1 bels (max)
500GB models	1.9 bels (typ)	2.7 bels (typ)
	2.3 bels (max)	3.0 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.

2.11TEST FOR PROMINENT DISCRETE TONES (PDTS)

Seagate follows the ECMA-74 standards for measurement and identification of PDTs. An exception to this process is the use of the absolute threshold of hearing. Seagate uses this threshold curve (originated in ISO 389-7) to discern tone audibility and to compensate for the inaudible components of sound prior to computation of tone ratios according to Annex D of the ECMA-74 standards.

2.12ELECTROMAGNETIC 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 7 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 1000 MHz, 3 V/m,		EN 61000-4-3: 96
	80% AM with 1 kHz sine	A
immunity			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
	0% short, 5 seconds	C	EN 61000-4-11: 94
interrupts	40%, 0.10 seconds	C
	70%, 0.01 seconds	B

CONSTELLATION ES SERIAL ATA PRODUCT MANUAL, REV. F 19