Acoustics; Electromagnetic Immunity - Seagate LD25 - Series 20 GB Hard Drive Product Manual

2.11

Acoustics

Drive acoustics are measured as overall A-weighted acoustic sound power levels. All measurements are con-
sistent 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 5: Drive level acoustics
Idle* Seek
2.4 bels (typ) 2.7 bels (typ)
*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.
2.12

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 6: Radio frequency environments
Test
Electrostatic discharge
Radiated RF immunity
Electrical fast transient
Surge immunity
Conducted RF immunity
Voltage dips, interrupts
A - 1) No upset or degradation in performance beyond manufacturer's specified limits.
2) No data loss.
B - 1) Unit self recovers without user intervention.
2) No data loss.
C - 1) Upset OK provided that unit will function after user intervention.
LD25 Series SATA Product Manual, Rev. C
Description
Contact, HCP, VCP: ± 4 kV; Air: ± 8 kV
80 to 1,000 MHz, 3 V/m,
80% AM with 1 kHz sine
900 MHz, 3 V/m, 50% pulse modulation @
200 Hz
± 1 kV on AC mains, ± 0.5 kV on external
I/O
± 1 kV differential, ± 2 kV common, AC
mains
150 kHz to 80 MHz, 3 Vrms, 80% AM with
1 kHz sine
0% open, 5 seconds
0% short, 5 seconds
40%, 0.10 seconds
70%, 0.01 seconds
Performance level Reference standard
B EN 61000-4-2: 95
A EN 61000-4-3: 96
ENV 50204: 95
B EN 61000-4-4: 95
B EN 61000-4-5: 95
A EN 61000-4-6: 97
C EN 61000-4-11: 94
C
C
B
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