Seagate ST31000640FC, ES.2 FC manual Physical/electrical specifications, AC power requirements

6.0Physical/electrical specifications

This section provides information relating to the physical and electrical characteristics of the drive.

6.1AC power requirements

None.

6.2DC power requirements

The voltage and current requirements for a single drive are shown below. Values indicated apply at the drive connector. Notes are shown following table 2.

Table 2: DC power requirements

			4 Gbit
		Notes	(Amps)	(Amps)
Voltage			+5V	+12V [2]
Regulation		[5]	±5%	±5% [2]
		[1] [6]	0.75	0.50
Avg idle current DCX
Maximum starting current
(peak DC) DC	3σ	[3]	1.00	2.00
(peak AC) AC	3σ	[3]	1.15	3.23
Delayed motor start (max) DC	3σ	[1] [4]	0.65	0.04
Peak operating current:
		[1]	0.69	0.77
Typical DCX
Maximum DC	3σ	[1]	0.71	0.82
Maximum (peak) DC	3σ		1.13	1.67

[1]Measured with average reading DC ammeter. Instantaneous +12V current peaks will exceed these val- ues. Power supply at nominal voltage. N (number of drives tested) = 6, 35 Degrees C ambient.

[2]For +12 V, a –10% tolerance is allowed during initial spindle start but must return to ±5% before reaching 10,000 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 +12V current profiles in Figure 1.

[4]This condition occurs when the Motor Start option is enabled and the drive has not yet received a Start Motor command.

[5]See paragraph 6.2.1, "Conducted noise immunity." Specified voltage tolerance includes ripple, noise, and transient response.

[6]During idle, the drive heads are relocated every 60 seconds to a random location within the band from

Barracuda ES.2 FC Product Manual, Rev. B 23