NEC N8405-019, User Manual

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Basic Features
This section describes basic features of the EM card.
Management Feature
Management features of the EM card are as follows:
Power Management
The EM card manages DC output of power supply 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 supply
units are installed in the Blade Enclosure and they are working normally, the EM card turns on the
DC output of two power supply units among them.
NOTE:
For the third and the subsequent power supply units, DC
output is turned on/off as needed.
The EM card manages the power consumption in the overall system.
The maximum power consumption available in the overall system varies depending on the power
capacity supplied to the system and the configuration of power supply 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 "blade enclosure maximum power consumption
management").
One of the following four upper limit values is used for blade enclosure maximum power
consumption management.
(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 of overall rack assembly or Blade Enclosure, regardless
of the configuration of power supply units or use of UPS Manager. See "Configuration File" in
Chapter 3 and "Configuration" in Chapter 4 for details.
(D) Upper limit determined by the capacity of built-in UPS unit (if installed).
See "Built-in UPS Unit" described later.
The EM card uses the value smallest among (A), (B), (C), and (D) as the upper limit value, and
performs blade enclosure maximum power consumption management of system power
consumption.
You can select a power redundancy mode (N+N redundant, N+1 redundant mode, or non-redundant
mode) and a power control policy ("CPU performance", "maintain redundancy" or "recover
redundancy" mode) as methods of power management by the EM card.