Cisco Laser Link Mainframes 安装指南
1-4
General Information
78-4004177-01 Rev D
Laser Link III Mainframe Description,
Continued
Fiber may be routed from the chassis through the bubble front of the door, through
ear holes on the side, or through the channel on the right side and out the rear of the
unit. Nineteen-inch rear support brackets are included and their use is
recommended.
Power Distribution
Main power can be universal AC,-48 V DC, or +24 V DC input. With universal AC
or -48 V DC, the Laser Link III chassis requires a power supply (converter). This unit
accepts the AC or the -48 V DC and performs the required conversion to output +24
V DC to the power distribution board (under which the power supply resides).
Should the +24 V DC be available, the mainframe can be operated without a power
supply by applying the voltage directly to the power distribution board.
Voltage applied to the power distribution board (+24 V DC) is routed to the various
Voltage applied to the power distribution board (+24 V DC) is routed to the various
modules installed in the mainframe. Each module requires this voltage for normal
operation. The power distribution board accepts +24 V DC as the primary input
power (supply A) through the connector labeled J10. The potential is then applied to
the modules through the interface cable provided with each module. This cable
connects the 26-pin interface on the mainframe to the rear panel power/status D
connector on the module. Fuse F2 protects the primary power (supply A). Fuse F5
is not applicable.
Redundant power (supply B) is provided in the form of +24 V DC to the terminal
Redundant power (supply B) is provided in the form of +24 V DC to the terminal
block of the power distribution board. The connecting point is labeled J11 and
accepts +24 V DC through a spade lug type of interface. The redundant input is also
load protected (fuse F1).