Seagate ST4000VM000 Acoustics, Test for Prominent Discrete Tones PDTs, Electromagnetic immunity

Drive Specifications www.seagate.com

2.10 Acoustics

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.

	For seek mode tests, the drive is placed in seek mode only. The number of seeks per second is defined by the
Note	following equation:
	(Number of seeks per second = 0.4 / (average latency + average access time)

Table 4 Fluid Dynamic Bearing (FDB) motor acoustics

Model	Idle*	Seek
ST2000VM003	2.1 bels (typ)	2.3 bels (typ)
	2.3 bels (max)	2.4 bels (max)
ST1000VM002	1.9 bels (typ)	2.2 bels (typ)
	2.1 bels (max)	2.3 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.

2.10.1 Test 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.

2.11 Electromagnetic 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 5 Radio frequency environments

Test	Description	Performance Level	Reference standard
Electrostatic	Contact, HCP, VCP: ± 4 kV; Air: ± 8 kV	B	EN61000-4-2: 95
discharge
Radiated RF	80MHz to 1,000MHz, 3 V/m,		EN61000-4-3: 96
	80% AM with 1kHz sine	A	ENV 50204: 95
immunity
	900MHz, 3 V/m, 50% pulse modulation @ 200Hz
Electrical fast	± 1 kV on AC mains, ± 0.5 kV on external I/O	B	EN61000-4-4: 95
transient
Surge immunity	± 1 kV differential, ± 2 kV common, AC mains	B	EN61000-4-5: 95
Conducted RF	150kHz to 80MHz, 3 Vrms, 80% AM with 1kHz	A	EN61000-4-6: 97
immunity	sine
	0% open, 5 seconds	C	EN61000-4-11: 94
Voltage dips,	0% short, 5 seconds	C
interrupts	40%, 0.10 seconds	C
	70%, 0.01 seconds	B

20 Video 3.5 HDD Product Manual, Rev. H