Seagate Exos 7E8 Serial ATA Product Manual, Rev. A
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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.
)
*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:
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
Table 3 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 4 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
