Power Supplies And Fan Cooling; Filler Panels - Sun Microsystems Enterprise 3500 System Reference Manual

D.5

Power Supplies and Fan Cooling

1. Requirement — The slot directly above a CPU/Memory+ board or I/O+ board
must contain a power/cooling module (PCM), because the fans in the PCM are
the only source of cooling air for the board slot.
2. Requirement — All unused slots must contain a filler panel to avoid loss of
cooling air.
3. Under some circumstances, you can remove a PCM from an active system for a
short time. However, if the boards in the adjacent slots create large quantities of
heat, it is safer to halt and power off the system first.
4. Requirement — The peripheral power supply/AC input (PPS/AC) must be fully
functional if you replace a hot-pluggable board or PCM. (Only the PPS/AC
provides precharge current to the system. If the PPS/AC cannot supply precharge
current, the hot-pluggable module will be damaged.)
5. Requirement — The slot above the PPS/AC must contain either a PCM or an
auxiliary fan tray.
6. The auxiliary peripheral power supply (PPS 1) is an option. The PPS 1 is located
at the front of the system, to the right of the disk drive area.
7. Requirement — If PPS 1 is absent, the slot must contain a thermal protection
module to ensure the maximum operating temperature is not exceeded.
8. PPS 1 does not provide precharge current.
D.6

Filler Panels

1. Requirement — Board filler panels are required for all unused board slots.
2. Requirement — PCM filler panels are required for all unused PCM bays.
3. Requirement — A thermal protection module must be installed if an auxiliary
peripheral power supply (PPS1) is not installed.
D-4 Sun Enterprise 3500 System Reference Manual • August 2001