16
ST12450W/WD Installation Guide, Rev. B
2
A –10% tolerance is permissible during initial start of the
spindle but must return to
±
5% before reaching 7,200 RPM.
The
±
5% must be maintained after the drive signifies that its
power-up sequence has been completed and that the drive
is able to accept selection by the host initiator.
3
See the +12V current profile in the
Barracuda 2, 2HP
Product Manual (publication number 83328900).
4
This condition occurs when the Motor Start option is en-
abled and the drive has not yet received a Start Motor
command.
5
See “Conducted noise immunity” in the
Barracuda 2, 2HP
Product Manual. The specified voltage tolerance is inclu-
sive of ripple, noise, and transient response.
6
At power-up, the motor current regulator limits the +12V
current to an average value of less than 2.0A, although
instantaneous peaks may exceed this value. These peaks
should measure 5 msec duration or less.
7
Minimum current loading for each supply voltage is not less
than 3% of the maximum operating current shown.
8
Use separate ground returns for +5 and +12V supplies.
9
Where power is provided to multiple drives from a common
supply, carefully consider individual-drive power require-
ments. Where multiple units are powered on simultaneously,
be sure the peak starting current is available to each device.
10
Operating condition is a third-stroke seek at OD and Read
One Track. The command is issued every 0.07 seconds for
ST12450WD models and every 0.075 seconds for
ST12450W models.
Summary of Contents for 2HP ST12450W/WD
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