Nortel Meridian 1 option 11C Planning And Installation Manual page 57

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• Leave adequate space for one or more expansion cabinets. When
possible, the expansion cabinets should be mounted next to each other
horizontally (horizontal expansion) to ensure proper heat dissipation.
• If horizontal expansion is not possible, vertical expansion is permitted
for two cabinets. Make sure the expansion cabinet is mounted above the
main cabinet.
Vertical expansion of three or more cabinets is not recommended. Such
a configuration makes reaching the top-most cabinet difficult.
Note: Temperature limits are more stringent when expanding vertically.
Review the temperature limits stated in the Environmental requirements
section of this guide before deciding to expand vertically. Do not install
an expansion cabinet on top of an existing floor-mounted cabinet.
• When planning for a system that is equipped with DTI/PRI capability,
allow space on the backboard for the channel service unit (CSU).
• Leave at least 6 in. (155 mm) above the mounting bracket and any
obstruction (such as a pipe or conduit) so that there is room to lift the
cabinet on and off the bracket.
• Leave at least 12 in. (305 mm) between the top of a cabinet and the
ceiling to ensure proper ventilation.
• Leave 10 in. (255 mm) between the bottom of the lower cabinet and the
floor to prevent water damage and to allow for convectional cooling.
• Do not place the cross-connect terminal above a cabinet. Debris from the
cross-connect terminal may drop into the cabinet through the top
ventilation slots and cause damage.
• Allow adequate space for the battery backup unit, accounting for the
cable-length limitation as determined by the choice of a wall-mounted or
floor-mounted battery back-up unit.
• If the NTAK92 Off-premises protection module is used, allow for proper
installation (according to local practices)
• Ensure power outlets are within reach of each system cabinet. Cable and
wire specifications are shown in Table 2, " Cable and wire
specifications," on page 32.
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