Nortel Networks DCT1900 Telephone User Manual


 
Technical Product Manual - DCT1900
Installation Instructions, Modular Cabinet Connection Board (MCCB) - ROANB 101 28
Install-DCT1900/R8/mw 17-1
© 2000-2005
CHAPTER 17
Modular Cabinet Connection Board (MCCB) - ROANB 101 28
17.1 Board Description
The MCCB (see Fig. 17–3) is installed on the bottom of the Modular Cabinet above the bottom
plate. The MCCB is used to make the following interconnections:
z Between the backplane power and a maximum of 3 CLUs/SLUs for powering Base Stations.
z Between the external power input and a maximum of 7 CLUs/SLUs for powering Base
Stations.
z Between the PBX signalling ground to a maximum of 7 LTUs when earth signalling is used
(instead of timed break signalling).
z Between the CPU, a PC, and a printer or TAP 1.8 compliant device.
z Between the general alarm output of the CPU and an alarm device.
A maximum of 3 CLUs/SLUs can be provided with Base Station power via the backplane. In that
case the 48V from the backplane is connected to the PW–BP input of the MCCB (see Fig. 17–1).
When more CLUs have to be powered, an external -48V power supply can be connected to the
PW–EXT input of the MCCB. In this way a maximum of 7 CLUs can be powered.