Chapter 2 Preparations
1.9
Power Supply Unit
The server has four slots for installing power supply units. Thus, the redundant power system can be configured by
installing hot-plug power supply units. This ensures continued operation of the system in the unlikely event one of the
redundant power supply units fails.
Install the power supply unit in the order power supply units 1, 3, 2, then 4.
•
N (Non-redundant):
Up to four units can be configured.
With non-redundant mode, the server can work with minimum requisite power supply units connected to
distribution board.
•
N+1 (Redundancy):
Operation can be continued even when one of power supply units fails.
For example, if the minimum requisite power supply units are two and one more unit is added, this enables
continuous operation by using the available two units even when one of three units fails.
•
2N (Redundancy):
Operation can be continued by supplying power to two power supply units from two electric power
companies respectively even in the case of power supply outage from one of the electric power companies.
The minimum requisite power supply units (N) depends on server model or configuration. Refer to System
Configuration Guide on the following URL.
http://www.nec.com/en/global/prod/express/collateral/configguide.html
Power supply
unit 1
Channel A
Important
If you select N (Non-redundant) or N+1 (Redundancy) as power supply unit
configuration, change Operation Mode [PSU Redundancy] to an appropriate setting
before the first power on. See Chapter 4 (2 Operation Mode (2) Remote Management)
for details.
Express5800/A1040b, A2040b, A2020b, A2010b User's Guide
1. Installing / Removing Internal Options
Power supply
Power supply
unit 2
unit 3
Channel B
Power supply
unit 4
175