Alcatel 7750 SR-12, Installation Manual

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Chassis Features
Page 14
7750 SR-12
C
HASSIS
F
EATURES
In the 7750 SR-12 chassis, the input/output module (IOM) slots are numbered 1 through 10. The
card slots are vertically oriented. A maximum of two MDAs can be installed on each IOM. MDAs
are installed in either MDA slot 1 (top slot) or MDA slot 2 (bottom slot) on an IOM.
A maximum of two SF/CPMs can be installed in the center SF/CPM slots which are designated as
slots A and B. At least one SF/CPM must be installed in order for the router to operate. The
redundant SF/CPM operates in standby mode and takes over system operation if the primary fails.
The 7750 SR-12 provides access to components from both the front and back sides. The filter tray,
SF/CPMs, IOMs, and MDAs are accessed from the front of the chassis. The power entry modules
(PEMs) and cooling trays (impeller trays) are accessible from the chassis rear.
Figure 1 and
Figure 2 show front and rear views.
DC PEMs are horizontally oriented and are accessed through the lower rear of the chassis. The
slots are designated as “1” for the top slot and “2” for the lower slot. The DC PEMs can be
connected directly to a DC power source. Optionally, power can be obtained through AC power
rectifiers.
The mounting brackets for the chassis are factory installed to mount in a standard 19-inch wide
rack. Refer to
Table 2 for key descriptions.