Acoustics; Electromagnetic Immunity; Test For Prominent Discrete Tones (Pdts) - Seagate Barracuda 7200.12 ST3320418AS Product Manual

2.9

Acoustics

Drive acoustics are measured as overall A-weighted acoustic sound power levels (no pure tones). All mea-
surements 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 latency + average access time)
Table 6: Fluid Dynamic Bearing (FDB) motor acoustics
All models
*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.
2.9.1

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.
2.10

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: Radio frequency environments
Test Description
Electrostatic Contact, HCP, VCP: ± 4 kV; Air: ± 8 kV
discharge
Radiated RF 80 to 1,000 MHz, 3 V/m,
immunity 80% AM with 1 kHz sine
900 MHz, 3 V/m, 50% pulse modulation @ 200 Hz
Electrical fast ± 1 kV on AC mains, ± 0.5 kV on external I/O
transient
Surge immunity ± 1 kV differential, ± 2 kV common, AC mains
Conducted RF 150 kHz to 80 MHz, 3 Vrms, 80% AM with 1 kHz sine A
immunity
Voltage dips, 0% open, 5 seconds
interrupts 0% short, 5 seconds
40%, 0.10 seconds
70%, 0.01 seconds
Barracuda 7200.12 Serial ATA Product Manual, Rev. B
Idle*
2.6 bels (typ)
2.7 bels (max)
Performance level
B
A
B
B
C
C
C
B
Seek
2.8 bels (typ)
3.0 bels (max)
Reference standard
EN 61000-4-2: 95
EN 61000-4-3: 96
ENV 50204: 95
EN 61000-4-4: 95
EN 61000-4-5: 95
EN 61000-4-6: 97
EN 61000-4-11: 94
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