Sun Microsystems 6.0005E+11 manual Power Requirements

6

The PCM incorporates an AC inrush limit circuit and two precharge inputs (3.3V and 5V) that enable it to be hot-pluggable into a live centerplane. A current sharing scheme on the 2.0V, 3.3V, and 5V outputs enable the PCM to operate in a parallel redundant mode. A maximum of eight PCMs are used together in the redundant current sharing.

The 5V output is parallel in a system with all other PCMs and the 5V output of a peripheral power supply. The 2.0V and 3.3V outputs are parallel in a system with all other PCMs.

6.4.1 Power Requirements

In general, if a PCM fails, the system boards will continue to be powered and cooled by the other power supplies provided redundancy (an additional power supply) is present. For example, if an Enterprise system needs a minimum of three power supplies and four are present, then the system has redundancy.

However, fully configured Enterprise systems represent a different situation and are always hot-pluggable. That is, an Enterprise 5000 or 4000 system with seven or eight boards and four PCMs is hot-pluggable. (The peripheral power supply acts as the “extra” power supply.) Similarly, an Enterprise 6000 system with fifteen or sixteen boards and eight power supplies is also hot-pluggable. (Only seven PCMs are required to power sixteen active boards; the eighth PCM is “extra.” However, the eighth PCM is required for cooling purposes.) See Table 6-3.

Note – The presence of an additional (extra) PCM in the system provides redundancy and allows hot-plug of PCMs.

Power Supplies 6-9