Heads Unload And Actuator Lock - Hitachi T7K250 - Deskstar - Hard Drive Specifications

The recommended mounting screw torque is 0.6 - 1.0 Nm (6-10 Kgf.cm).
The recommended mounting screw depth is 4 mm maximum for bottom and 4.5 mm maximum for horizontal
mounting.
Drive level vibration test and shock test are to be conducted with the drive mounted to the table using the bottom
four screws.

7.5.5 Heads unload and actuator lock

The head load/unload mechanism is provided to protect the disk data during shipping, movement, or storage. Upon
power down, the heads are automatically unload from the disk area and the locking mechanism of the head actuator
will secure the heads in unload position.
Deskstar T7K250 Hard Disk Drive Specification
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