User's Guide

23
Basic Features
This section describes the basic feature of the EM card.
Management Features
The below describes the management features of the EM card.
Power Management
The EM card manages DC output of power unit(s) in the Blade Enclosure. When the AC power is
supplied to the Blade Enclosure, the EM card starts operating. If two or more power units are installed
in the Blade Enclosure and they are working normally, the EM card turns on the DC output of two
power units among them.
TIPS:
For the third and the subsequent power units, DC output is turned on /off as needed.
The EM card manages the power consumption in the entire system.
The maximum power consumption available in the entire system varies depending on the power
capacity supplied to the system and the configuration of power units (including types and number of
units).
The maximum power consumption management is to manage the power consumption of each of the
modules configuring the system so that the maximum power consumption in the system is maintained
within a certain value (called as “ceiling control”).
One of the following three upper limit values is used for ceiling control.
A. Upper limit determined by the types, number of power supply units, and input voltage.
B. If the UPS is managed by EM card, the EM card calculates the upper limit based on the type of
UPS connected.
C. Upper limit specified for input voltage regardless of the configuration of power units or use of
UPS manager. See “Configuration File” in Chapter 3 and “Configuration” in Chapter 4 for details.
The EM card uses the value smallest among A, B and C as the upper limit value, and performs ceiling
control system power consumption.
You can select a power redundancy mode (N+N redundant or N+1 redundant mode) and a power
control policy (CPU performance, “maintain redundancy” or “recover redundancy” mode) as methods
of power management by the EM card.