Seagate BARRACUDA 4LP ST34571N/W/WC/WD/DC - Manual (Page 17)

Barracuda 4LP Installation Guide, Rev. B 15
Table 2b. DC power requirements (Amps)
[1] Measured with an average reading DC ammeter. Instanta-
neous +12V current peaks will exceed these values.
[2] A –10% droop 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 4LP Product
Manual (publication number 77767491).
[4] This condition occurs when the Motor Start option is enabled
and the drive has not yet received a Start Motor command.
ST32171/ST32271
N/W/WC
Single-ended
WD/DC
Differential
Voltage +5V +12V +5V +12V
Regulation [5] ±5% ±5% [2] ±5% ±5%[2]
Max. operating current
DC3
σ
[1] 0.81 0.85 1.21 0.85
Avg. idle current DCX [1] 0.46 0.52 0.70 0.52
Max. starting current
(peak DC) DC3
σ
[3]
(peak AC) AC3
σ
[3]
0.78 2.00
3.1 1.1 2.00
3.1
Delayed motor start (max)
DC3
σ
[1][4] 0.50 0.20 0.90 0.20
Peak operating current
Typical DCX [1] [6]
Maximum DC3
σ
[1]
Maximum (peak) 3
σ
0.72
0.81
1.5 0.73
0.85
2.3 0.91
1.21
2.0 0.73
0.85
2.3