Replacing a hot-swap DC power supply

To install a hot-swap DC power supply, complete the following steps.

• Only trained service personnel other than Lenovo service technicians are authorized to install and remove the -48 volt DC power supply, and make the connections to and disconnections from the -48 volt DC power source. Lenovo service technicians are not certified or authorized to install or remove the -48 volt power cable. The customer is responsible for ensuring that only trained service personnel install or remove the -48 volt power cable.
• Before you install a DC power supply in the server, you must remove all AC power supplies. Do not use both AC and DC power supplies in the same server. Install six DC power supplies or six AC power supplies, but not a combination.
• If you need to order more ferrite clamp cores, the part number is 94Y8175.

Regulations

• It is the customer's responsibility to supply the necessary power cable.
  To reduce the risk of electric shock or energy hazards:

  • Use a circuit breaker that is rated at 70 amps.
  • Use 4 mm² (10 AWG) at 90° C copper wire.
  • Torque the wiring-terminal screws to 0.50 ~ 0.60 newton-meters (4.43 ~ 5.31 inch-pounds).

  For more information, see Statement 34.
• If the power source requires ring terminals, you must use a crimping tool to install the ring terminals to the power cord wires. The ring terminals must be UL approved and must accommodate the wire that is described in the above-mentioned note.
• To avoid radiated emission, you must attach a clamp core for each of the 900 W DC power supply used.
  Figure 1. Ferrite clamp core
  
  

Statement 29

CAUTION: This equipment is designed to permit the connection of the earthed conductor of the DC supply circuit to the earthing conductor at the equipment.

This equipment is designed to permit the connection of the earthed conductor of the DC supply circuit to the earthing conductor at the equipment. If this connection is made, all of the following conditions must be met:

• This equipment shall be connected directly to the DC supply system earthing electrode conductor or to a bonding jumper from an earthing terminal bar or bus to which the DC supply system earthing electrode conductor is connected.
• This equipment shall be located in the same immediate area (such as, adjacent cabinets) as any other equipment that has a connection between the earthed conductor of the same DC supply circuit and the earthing conductor, and also the point of earthing of the DC system. The DC system shall not be earthed elsewhere.
• The DC supply source shall be located within the same premises as this equipment.
• Switching or disconnecting devices shall not be in the earthed circuit conductor between the DC source and the point of connection of the earthing electrode conductor.

Statement 31

DANGER

danger

Electrical current from power, telephone, and communication cables is hazardous.

To avoid a shock hazard:

• Do not connect or disconnect any cables or perform installation, maintenance, or reconfiguration of this product during an electrical storm.
• Connect all power cords to a properly wired and grounded power source.
• Connect to properly wired power sources any equipment that will be attached to this product.
• When possible, use one hand only to connect or disconnect signal cables.
• Never turn on any equipment when there is evidence of fire, water, or structural damage.
• Disconnect the attached ac power cords, dc power sources, network connections, telecommunications systems, and serial cables before you open the device covers, unless you are instructed otherwise in the installation and configuration procedures.
• Connect and disconnect cables as described in the following table when you install, move, or open covers on this product or attached devices.

To Connect:

To Disconnect:

Turn OFF all power sources and equipment that is to be attached to this product. Attach signal cables to the product. Attach power cords to the product. For ac systems, use appliance inlets. For dc systems, ensure correct polarity of -48 V dc connections: RTN is + and -48 V dc is -. Earth ground should use a two-hole lug for safety. Attach signal cables to other devices. Connect power cords to their sources. Turn ON all the power sources.

Turn OFF all power sources and equipment that is to be attached to this product. For ac systems, remove all power cords from the chassis power receptacles or interrupt power at the ac power distribution unit. For dc systems, disconnect dc power sources at the breaker panel or by turning off the power source. Then, remove the dc cables. Remove the signal cables from the connectors. Remove all cables from the devices.

Statement 33

CAUTION

This product does not provide a power-control button. Turning off blades or removing power modules and I/O modules does not turn off electrical current to the product. The product also might have more than one power cord. To remove all electrical current from the product, make sure that all power cords are disconnected from the power source.

Statement 34

CAUTION

To reduce the risk of electric shock or energy hazards:

• This equipment must be installed by trained service personnel in a restricted-access location, as defined by the NEC and IEC 60950-1, First Edition, The Standard for Safety of Information Technology Equipment.
• Connect the equipment to a properly grounded safety extra low voltage (SELV) source. A SELV source is a secondary circuit that is designed so that normal and single fault conditions do not cause the voltages to exceed a safe level (60 V direct current).
• Incorporate a readily available approved and rated disconnect device in the field wiring.
• See the specifications in the product documentation for the required circuit-breaker rating for branch circuit overcurrent protection.
• Use copper wire conductors only. See the specifications in the product documentation for the required wire size.
• See the specifications in the product documentation for the required torque values for the wiring-terminal screws.

1. Read the safety information that begins on Safety and Installation guidelines.
2. Touch the static-protective package that contains the hot-swap power supply to any unpainted metal surface on the server; then, remove the power supply from the package and place it on a static-protective surface.
3. Turn off the circuit breaker for the DC power source to which the new power supply will be connected. Disconnect the power cord from the DC power source.
4. Attach the DC power cable to the new power supply.
   Figure 2. DC power supply rear view
   
   
5. If you are installing a hot-swap power supply into an empty bay, remove the power-supply filler from the power-supply bay.
6. Grasp the handle on the rear of the power supply and slide the power supply forward into the power-supply bay until it clicks. Make sure that the power supply connects firmly into the power-supply connector.
   Figure 3. Power supply installation
   
   
7. Route the power cord through the handle and cable tie if any, so that it does not accidentally become unplugged.
8. Connect the other ends of the DC power cable to the DC power source. Cut the wires to the correct length, but do not cut them shorter than 150 mm (6 inch). If the power source requires ring terminals, you must use a crimping tool to install the ring terminals to the power cord wires. The ring terminals must be UL approved and must accommodate the wires that are described in Regulations. The minimum nominal thread diameter of a pillar or stud type of terminal must be 4 mm; for a screw type of terminal the diameter must be 5.0 mm.
9. Attach the ferrite clamp core nearly to power supply with all input cables including the -48V, the -48V RTN, and the ground cable.
10. Turn on the circuit breaker for the DC power source to which the new power supply is connected.
11. Make sure that the green power LEDs on the power supply are lit, indicating that the power supply is operating correctly.
12. If you are adding a power supply to the server, attach the redundant power information label that comes with this option on the server cover near the power supplies.
    Figure 4. Redundant power information label