The Origin 3900 server uses the following power components: power distribution units (PDUs), power distribution strips (PDSs), and power bays. This chapter describes the function and physical aspects of these power components in the following sections:
The power bay, which is a 3U-high enclosure, can monitor, control, and supply AC power to as many as six hot-swappable distributed power supplies (DPSs). The number of power supplies depends on the rack type. For example, in an I/O rack, the power bay has four power supplies. In racks that house Cx-bricks and/or R-bricks, the power bay has six power supplies.
Each DPS inputs single-phase AC voltage and outputs 950 W at 48 VDC and 42 W at 12 VDC. The outputs of the DPSs are bused together. For example, when the power bay contains six DPSs, the DPSs are bused together to provide approximately 5,380 W of 48-VDC power and 282 W of 12-VDC power.
This section describes the external components located on the front and rear panels of the power bay.
The front of the power bay seats the distributed power supplies (see Figure 9-1). When the power bay contains four power supplies, the supplies reside in locations 3, 4, 5, and 6 (the four supplies on the right).
The rear of the power bay has eight DC output connectors (see Figure 9-2). A power cord connects one output connector to a Cx-brick, R-brick, or I/O brick. This connection provides 12-VDC standby power, 48-VDC power, and monitoring signals.
 | Note: The L1 controller of a connecting module can monitor the status and enable the output ports of the power bay. |
The power bay module also has six AC input connectors, one for each power supply location. For example, when the power bay contains four power supplies, connectors 3, 4, 5, and 6 (the four connectors on the left) connect to the power distribution unit (PDU). When the power bay contains six power supplies, connectors 1 and 2 also connect to the PDU.
The reset button resets the power bay when a fault condition occurs.
The distributed power supplies (DPSs) are air-cooled devices; each DPS has two fans that move air from the front of the rack to the rear of the rack. Figure 9-3 shows the front view of a DPS.
Each DPS has the following LEDs:
Table 9-1 lists conditions of the power supplies and the corresponding states of the LEDs.
Table 9-1. Power Supply LED States
| LED States |
|
|
|---|---|---|---|
Power Supply Condition | Power (Green) | PFAIL (Amber) | FAIL (Amber) |
AC voltage not applied to all power supplies | Off | Off | Off |
AC voltage not applied to this power supply | Off | Off | On |
AC voltage present; standby voltage on | Blinking | Off | Off |
Power supply DC outputs on | On | Off | Off |
Power supply failure | Off | Off | On |
Current limit reached on 48-VDC output | On | Off | Blinking |
Predictive failure | On | Blinking | Off |
Each power supply also contains a serial ID EEPROM that identifies the model and serial number of the supply. The L1 controller of a connecting module reads this information.
Table 9-2 lists the specifications of the power bay.
Table 9-2. Power Bay Technical Specifications
Characteristic | Specification |
|---|---|
Height | 5.12 in. (130.04 mm) |
Width | 17.5 in. (444.5 mm) |
Depth | 23.87 in. (606.3 mm) |
Weight | 64.5 lb (29.26 kg) |
Input voltage | 220 VAC |
Output voltage | 12 VDC and 48 VDC |
Table 9-3 lists the specifications of the distributed power supplies.
Table 9-3. Power Supply Technical Specifications
Characteristic | Specification |
|---|---|
Height | 5 in. (127 mm) |
Width | 2.8 in. (71.12 mm) |
Depth | 13 in. (330.2 mm) |
Weight | 7.5 lb (3.40 kg) |
Input voltage | 220 VAC |
Output voltage | 12 VDC and 48 VDC |
A PDU filters input power, protects against over-current conditions, and provides a power switch to remove power from a rack.
The Origin 3900 server supports a single-phase and a three-phase PDU. A system that uses single-phase power requires one single-phase PDU for each power bay (see Figure 9-4). A system that uses three-phase power requires one three-phase PDU per rack.
The power distribution strip has six output power receptacles, one input power receptacle, and one 10-A circuit breaker. This strip is required when there are components within the rack that need 220 VAC (for example, disk storage modules). The power strip has a rating of 200 - 250 VAC.
