2.11Acoustics

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.

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 5: Drive level acoustics

Idle*

Performance Seek

 

 

2.4 bels (typ)

2.9 bels (typ)

2.6 bels (max)

3.1 bels (max)

 

 

Note. *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.

2.12Electromagnetic 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 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 1,000 MHz, 3 V/m,

A

EN 61000-4-3: 96

 

 

80% AM with 1 kHz sine

 

ENV 50204: 95

 

 

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

 

 

 

 

200 Hz

 

 

 

 

 

 

Electrical fast transient

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

B

EN 61000-4-4: 95

 

 

O

 

 

 

 

 

 

Surge immunity

± 1 kV differential, ± 2 kV common, AC

B

EN 61000-4-5: 95

 

 

mains

 

 

 

 

 

 

Conducted RF immunity

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

A

EN 61000-4-6: 97

 

 

1 kHz sine

 

 

 

 

 

 

Voltage dips, interrupts

0% open, 5 seconds

C

EN 61000-4-11: 94

 

 

0% short, 5 seconds

C

 

 

 

40%, 0.10 seconds

C

 

 

 

70%, 0.01 seconds

B

 

 

 

 

 

 

Momentus 5400.2 SATA Product Manual, Rev. C

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Seagate ST96812AS, ST98823AS manual Acoustics, Electromagnetic immunity, Drive level acoustics, Radio frequency environments