3.3 Servicing Power Supplies (CRU)

The power supplies on the Sun Fire X4470 Server are redundant. That is, the server needs only one power supply to operate. Redundant power supplies enable you to remove and replace a power supply without shutting down the server, provided that the other power supply is online and working.

The server offers two redundancy modes for the power supplies. Light load efficiency mode (LLEM) places PS1 in a warm standby condition while PS0 carries the entire load more efficiently by itself. If PS0 loses AC power or is extracted for replacement, PS1 takes over the load automatically. Some rare internal failures of PS0 could cause the server to lose power faster than PS1 can take over.Disabling the LLEM Policy causes the power supplies to share the load at all times, at the expense of efficiency during light loads. For information about configuring policies, refer to the Oracle Integrated Lights Out Manager (ILOM) 3.0 Supplement for Sun Fire X4470 Server (821-0702).

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Dikkat - If a power supply fails and you do not have a replacement available, to ensure proper airflow, leave the failed power supply installed in the server until you replace it with a new power supply.

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This section describes how to remove and install power supplies.

3.3.1 Power Supply LED Reference

Each power supply contains a series of LEDs on the back panel of the system as shown in Power Supply Status LEDs .

Figure 3-7 Power Supply Status LEDs

Power Supply Status LED Descriptions describes the functions of the LEDs.

Table 3-3 Power Supply Status LED Descriptions

Legend LED Symbol Color Lights When... 1 Service Action Required Amber The power supply is faulty. Service action is required. 2 DC OK Green Both DC outputs (3.3V standby and 12V main) are active and within regulation. 3 AC OK Green or Amber Green: AC voltage within operating range is applied to the power supply. Amber: AC range below operating range is applied to the power supply.

3.3.2 Detecting a Power Supply Failure

The following LEDs are lit when a power supply fault is detected:

• Front and rear Service Action Required LEDs

• Rear PS Fault LED on the front bezel of the server

• Service Action Required LED on the faulty power supply

See 1.2 Server Front Panel Features and 1.3 Server Back Panel Features for locations of system LEDs.

3.3.3 Removing and Installing Power Supplies

Use the following procedures to remove and install power supplies.

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Caution - Hazardous voltages are present. To reduce the risk of electric shock and danger to personal health, follow the instructions.

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Remove a Power Supply

Refer to Removing a Power Supply when completing the following procedure.

1. Prepare for servicing:
   1. Attach an antistatic wrist strap.

      See 2.3 Performing Electrostatic Discharge and Static Prevention Measures.

   2. If necessary, release the cable management arm to access the power supplies.

      See 2.5 Releasing the Cable Management Arm.

2. Identify which power supply (0 or 1) requires replacement.

   A lit Service Action Required LED on a power supply indicates that a failure was detected.

3. Disconnect the power cord from the faulty power supply.
4. Press down on the release latch.
5. Slide the power supply out of the chassis.

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   Caution - Whenever you remove a power supply, you should replace it with another power supply; otherwise, the server might overheat due to improper airflow. If a new power supply is not available, leave the failed power supply installed until it can be replaced.

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   Figure 3-8 Removing a Power Supply

   

Install a Power Supply

Refer to Installing a Power Supply when completing this procedure.

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Caution - Install an A239A or A239C power supply, labeled for upright installation, in the Sun Fire X4470 Server. The A239A/A239C power supply correctly exhausts air from the rear of the server. Do not install an A239 or A239B power supply, which might cause the system to overheat and shut down.

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1. Align the power supply with the empty power supply chassis bay.
2. Slide the power supply into the bay until it is fully seated.
3. Move the release latch up to secure the power supply in place.
   

   Figure 3-9 Installing a Power Supply

   
4. Reconnect the power cord to the power supply.
5. Verify that the AC Present LED is lit.

   See 3.3.1 Power Supply LED Reference.

6. Verify that the following LEDs are not lit:

   • Service Action Required LED on the power supply

   • Front and rear Service Action Required LEDs

   • Rear PS Failure LED on the bezel of the server

     See 1.2 Server Front Panel Features and 1.3 Server Back Panel Features for locations of system LEDs.