Seagate ST680712DEG, ST660712DE manual Acoustics, Electromagnetic immunity, Drive level acoustics

2.9Acoustics

Drive acoustics are measured as overall A-weighted acoustic sound power levels (no pure tones). Discrete tone penalties are added to the A-weighted sound power (LW) with the following formula only when determin- ing compliance:

LWt(spec) == LW + 0.1Pt + 0.3 < 4.0 (Bels) where

LW = A-weighted sound power level

pt == Value of discrete tone penalty [==dLt-6.0 (dBA)]

dLt = Tone-to-noise ratio taken in accordance with ISO 7779.

All measurements 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: Drive level acoustics

Acoustic mode

Idle	Operational
1.6 bels (typ)	1.9 bels (typ)
1.7 bels (max)	2.0 bels (max)

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 7:	Electromagnetic immunity
			Performance	Reference
Test		Description	level	standard
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/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	A	EN 61000-4-6: 97
		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

ST1.3 Series Product Manual, Rev. C 15