Seagate Exos X20 SATA Product Manual, Rev. B
18
www.seagate.com
Drive specifications
2.7
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.
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 l average access time
)
*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
.
2.8
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.
2.9
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 7 Fluid Dynamic Bearing (FDB) motor acoustics
Idle*
Performance seek
All models
2.8 bels (typ)
3.0 bels (max)
3.2 bels (typ)
3.4 bels (max)
Table 8 Radio frequency environments
Test
Description
Performance level
Reference standard
Electrostatic discharge
Contact, HCP, VCP: ± 4
kV; Air:
± 8 kV
B
EN 61000-4-2: 95
Radiated RF immunity
80 to 1000 MHz, 3 V/m,
80% AM with 1 kHz sine
900 MHz, 3 V/m, 50% pulse modulation @ 200 Hz
A
EN 61000-4-3: 96
ENV 50204: 95
Electrical fast transient
± 1 kV on AC mains, ± 0.5 kV on external I/O
B
EN 61000-4-4: 95
Surge immunity
± 1 kV differential, ± 2 kV common, AC mains
B
EN 61000-4-5: 95
Conducted RF immunity
150 kHz to 80 MHz, 3 Vrms, 80% AM with 1 kHz sine
A
EN 61000-4-6: 97
Voltage dips, interrupts
0% open, 5 seconds
0% short, 5 seconds
40%, 0.10 seconds
70%, 0.01 seconds
C
C
C
B
EN 61000-4-11: 94
