Troubleshooting power issues

Properly configured BladeCenter® chassis provide power redundancy by supplying power to each chassis component from two or more power modules. BladeCenter chassis are connected to either AC current or DC current.

Note: (DC Current) Only trained service personnel, other than IBM service technicians, are authorized to make the connections to and disconnections from the -48 volt DC power source. IBM 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.

All AC current chassis except the BCS require 220 Volt AC input. The BCS chassis has auto sensing power modules which can be connected to either 110 Volt or 220 Volt AC power. Do not mix input voltages on a BCS chassis.

Each AC power module has an AC (in) and DC (out) power LED. The AC (in) power LED will be illuminated when the power module is properly connected to a power source. If the AC (in) power LED is not illuminated, inspect the complete path from the actual power source to the power module. Verify functionality of all components including the circuit breakers, wall or floor power outlets, Power Distribution Units (PDU), and power cables. Power cable specifications depend on the chassis type/model and vary in the number and style of connectors.

Note: Every power cord must be connected to a power source.

Configurations may include redundant power sources to a single chassis. AC power modules convert the AC input current to DC output current. The DC (out) power LED will be illuminated when the power module is distributing DC power to the chassis midplane. If it is not illuminated:

Remove AC power cable from the power source.
Remove and visually inspect the connections on the power module and the chassis.
Reseat the power module and reconnect the power cable at the source.

Further troubleshooting should be performed by IBM service technicians.

Some power modules also have a Fault LED. Verify the power input configuration before replacing a power module with an illuminated Fault LED.

Note: Before removing AC power from a power module or removing a power module from the chassis, verify that the capacity of the remaining power modules are sufficient to meet the minimum power requirements for all installed components

View power status and requirements in the advanced management module. Basic problem determination should include swapping suspect bad power cables/sources/power modules with known good units for verification whenever possible. The advanced management module polls the power modules over multiple I²C busses. Details such as power module status, available power and all relevant hardware and firmware VPD can be viewed from the advanced management module.

The advanced management module has configurable power management policy settings. Power policy options vary by chassis type/model. Power policies are selected based on configuration specifics such as installed power modules, actual and estimated power consumption, the number and type of power sources, and the production roles of the blades servers. Power management policies primarily control how blade servers react to changes in available power, i.e. situations such as the loss of a power module or power source.

Note: The most restrictive power policy combined with certain chassis configurations may limit the number of blade servers allowed to power on. For more information about power management policies, see the Help section within the advanced management module or the IBM BladeCenter Advanced Management Module User's Guide.