Seagate ST31000528AS Barracuda 7200.12 SATA Product Manual - Page 23

2.9 Acoustics Drive acoustics are measured as overall A-weighted acoustic sound power levels (no pure tones). 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: Fluid Dynamic Bearing (FDB) motor acoustics All models Idle* 2.6 bels (typ) 2.7 bels (max) Seek 2.8 bels (typ) 3.0 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. 2.9.1 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 Electrostatic discharge Radiated RF immunity Electrical fast transient Surge immunity Conducted RF immunity Voltage dips, interrupts Description Contact, HCP, VCP: ± 4 kV; Air: ± 8 kV 80MHz to 1,000MHz, 3 V/m, 80% AM with 1kHz sine 900MHz, 3 V/m, 50% pulse modulation @ 200Hz ± 1 kV on AC mains, ± 0.5 kV on external I/O ± 1 kV differential, ± 2 kV common, AC mains 150kHz to 80MHz, 3 Vrms, 80% AM with 1kHz sine 0% open, 5 seconds 0% short, 5 seconds 40%, 0.10 seconds 70%, 0.01 seconds Performance level B A B B A C C C B Reference standard EN61000-4-2: 95 EN61000-4-3: 96 ENV50204: 95 EN61000-4-4: 95 EN61000-4-5: 95 EN61000-4-6: 97 EN61000-4-11: 94 Barracuda 7200.12 Serial ATA Product Manual, Rev. G 17