2.9Acoustics

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 3:

Fluid Dynamic Bearing (FDB) motor acoustics

 

 

 

 

 

 

 

Idle*

CE Seek

 

 

 

 

1000 GB model

2.9 bels (typ)

3.1 bels (typ)

3.1 bels (max)

3.2 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.

2.9.1Test 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.

2.10Electromagnetic 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 4:

Radio frequency environments

 

 

 

 

 

 

 

Test

 

Description

Performance level

Reference standard

 

 

 

 

 

Electrostatic

 

Contact, HCP, VCP: ± 4 kV; Air: ± 8 kV

B

EN 61000-4-2: 95

discharge

 

 

 

 

Radiated RF

 

80 to 1,000 MHz, 3 V/m,

A

EN 61000-4-3: 96

immunity

 

80% AM with 1 kHz sine

 

ENV 50204: 95

 

 

900 MHz, 3 V/m, 50% pulse modulation @ 200 Hz

 

 

Electrical fast

± 1 kV on AC mains, ± 0.5 kV on external I/O

B

EN 61000-4-4: 95

transient

 

 

 

 

Surge immunity

± 1 kV differential, ± 2 kV common, AC mains

B

EN 61000-4-5: 95

 

 

 

 

Conducted RF

150 kHz to 80 MHz, 3 Vrms, 80% AM with 1 kHz sine

A

EN 61000-4-6: 97

immunity

 

 

 

 

Voltage dips,

 

0% open, 5 seconds

C

EN 61000-4-11: 94

interrupts

 

0% short, 5 seconds

C

 

 

 

40%, 0.10 seconds

C

 

 

 

70%, 0.01 seconds

B

 

12

Pipeline HD Pro Serial ATA Product Manual, Rev. C

Page 18
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Seagate ST31000533CS manual Acoustics, Electromagnetic immunity, Fluid Dynamic Bearing FDB motor acoustics