3 powering base stations via the modular cabinet, 1 -48v external source powering, 1 –48v external source powering – Nortel Networks DCT1900 User Manual

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Technical Product Manual - DCT1900

Configuration Directions, Base Station Powering

4-2

Config-DCT1900/R8/mw

Fig. 4–1 Powering Base Stations by a remote Supply

4.3

Powering Base Stations via the Modular Cabinet

Base Stations are powered via the following path:

External source-MCCB-CLU/SLU-Base Station

Base Stations are connected to the CLU or SLU via an MDF by 2, 3 or 4 twisted pair cables. The
maximum permissible length depends on the wire size and the number of pairs used between the
MDF and Base Station. The CLU/MDF cable contains only one Express Powering Pair (EPP), but
this may be doubled up on the MDF. Table 4–2 shows the maximum cable lengths.

4.3.1 –48V External Source Powering

Via an external -48V source, any configuration of cabinets and Base Stations can be powered as
long as the power specifications of the external source are met. This method is suitable for any
situation where PBX power is available (see Figure 4–2) or any other -48V supply with sufficient
current capacity. The maximum cable lengths are given in Table 4–2 (42V and 48V column).

Fig. 4-2 Modular Cabinets powered by PBX

Local
Power

Radio

Exchange

Base
Station

SC0

SC1

EPP

data pair

PBX

CAB