Seagate ST9160827AS ユーザーズマニュアル

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Momentus 5400.4 SATA Product Manual, Rev. A
13
2.11
Acoustic emission
Drive emission of sound is measured consistent with the ECMA-74 and its’ referenced standards. Testing is 
conducted at room temperature (approximately 25C). Emissino levels are reported as the total A-weighted 
sound power levels for, steady state, idle and active (seek) modes of operations.
*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.
Test for Prominent Discrete Tones (PDTs)
Seagate follows the ECMA-74 standards for measurement and identification of PDTs. An exception to this pro-
cess is the use of the absolute threshold of hearing. Seagate uses the lower limit for the threshold curve* 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.
* Defined as the median curve given by ISO 389-7 (Tf curve) minus 10dB at all frequencies.
2.12
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: 
Drive level acoustics
Models
Idle*
Performance seek
2 discs
ST9250827AS
 
ST9200827AS
 
ST9160827AS
2.4 bels (typ)
 
2.6 bels (max)
2.6 bels (typ)
 
2.8 bels (max)
1 disc
ST9120817AS
2.2 bels (typ)
 
2.4 bels (max)
2.9 bels (typ)
 
3.1 bels (max)
Table 6: 
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 2,000 MHz, 10 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
Power Frequency H-field 
immunity
1 A/m, 50Hz/60Hz, 3 axes
A
EN 61000-4-8: 97
Voltage dips, interrupts
30% Reduction for 25 cycles
 
>95% Reduction for 250 cycles
 
>95%, 0.5 cycles
C
 
C
 
B
EN 61000-4-11: 94