Nortel Passport 15000, Установка и обслуживание оборудования, Страница: 68 / 874

68 Chapter 2 Safety considerations and best practices
241-1501-240 5.2S2
With the power interface modules (PIMs) that distribute power from the BIP
to the shelves, each module must be unplugged before it can be removed. This
is a personal safety action because of the amount of voltage that feeds each
PIM. Since each cage of a shelf has a pair of redundant PIMs, unplugging one
does not affect power to the cage.
Although a fan must be unplugged before removing it to replace it or to access
its controller, it is considered hot-swappable because the power to the cooling
unit remains on.
Packing and unpacking a processor card or module
Use the procedure “Unpacking a processor card or module” (page 867) for a
new or re-deployed card immediately prior to the installation procedure, or to
verify a shipment. If you unpack to verify a shipment, always re-pack the
item. Repackaging protects the item, especially from ESD.
Use the procedure “Packing a processor card or module” (page 642) for a
failed or re-deployed card immediately following a removal procedure.
Processor card compatibility
When choosing a processor card to replace, upgrade, or downgrade another
card in a slot, the card (new or redeployed) must have a compatible or
equivalent product engineering code (PEC). In general, for control processors
(CPs) to be considered compatible, all eight alphanumerical characters of the
PECs must match. For function processors (FPs) to be considered compatible,
the first six alphanumerical characters of the PECs must match.
A compatible card or module
• has a PEC with the same first six alphanumerical characters
• typically has more or less functionality distinguished by version
increments (for example, an AB card can have more capacity than its AA
version)
• usually can be replaced only one way, that is, from an older to a newer
vintage (for example, AA to AB) or lower to higher performance
specifications (for example, AA to CA), especially if the card slot
requires additional software configuration for optimum operation