Hitachi HDT725025VLA380 Specifications - Page 76

7.6.3 Operating shock The drive meets the following criteria while operating in the conditions described below. The shock test consists of 10 shock inputs in each axis and direction for total of 60. There must be a delay between shock pulses long enough to allow the drive to complete all necessary error recovery procedures. • No error occurs with a 10 G half-sine shock pulse of 11 ms duration in all models. • No data loss occurs with a 30 G half-sine shock pulse of 4 ms duration in all models. • No data loss occurs with a 70 G half-sine shock pulse of 2 ms duration in all models. 7.6.4 Nonoperating shock The drive will operate with no degradation of performance after being subjected to shock pulses with the following characteristics. 7.6.4.1 Trapezoidal shock wave • Approximate square (trapezoidal) pulse shape • Approximate rise and fall time of pulse is 1 ms • Average acceleration level is 50 G. (Average response curve value during the time following the 1 ms rise time and before the 1 ms fall with a time "duration of 11 ms") • Minimum velocity change is 4.23 meters per second 7.6.4.2 Sinusoidal shock wave The shape is approximately half-sine pulse. The figure below shows the maximum acceleration level and duration. Table 45: Sinusoidal shock wave Models Acceleration level (G) Duration (ms) 2 disk 350 2 3 disk 300 2 All models 150 11 7.6.5 Nonoperating rotational shock All shock inputs shall be applied around the actuator pivot axis. Table 46: Rotational shock Duration 1 ms 2 ms Rad/s2 30,000 20,000 Deskstar T7K500 Hard Disk Drive Specification 62