Install Manual

BRITECELL System Manual MN010-04 June 2003 Page 65 of 78
The company has a policy of continuous product development and improvement and we therefore
reserve the right to vary any information quoted without prior notice.
58.4. Power Supply
A Britecell system may be locally (at each remote unit) or distributed powered.
There are advantages with both methods. It may be faster and cheaper to use
local power, however it is easier to back-up a system when the power originates at
a single point. A power supply may be distributed in a composite cable (copper
and fiber), or two separately parallel cables may be run. Note that the cable
containing the copper conductors must carry the appropriate plenum rating and
must be of sufficient conductor area to ensure adequate voltage at the furthest
Remote Unit under full load. Refer to TFA datasheet for power consumption
specifications.
If Local Units subrack is to be co-located with a BTS it is often desirable to power
the entire system from the battery-backed low voltage supply available. The Local
Unit card is fitted with a universal AC power supply module but can be ordered
with -48VDC modules instead. The overall power consumption of a full equipped
subrack will not exceed 110W.
A general rule for subrack power consumption is:
(Local Unit consumption [W]) x (cards number) / 0.75 = overall consumption [W]
59. SYSTEM START-UP
In order to avoid damaging the equipment, the following criteria must be used
to start up the system:
1. Verify all the power supply connections.
2. Verify all the RF connections.
3. Verify all the optical connections.
4. Set all the adjustable attenuators on the TFL-BSI at the maximum value of
attenuation.
5. Switch on the local units sub-racks.
6. Check for alarm status and in case of alarm refer to troubleshooting
paragraph.
7. Connect the spectrum analyser at the input of one TFL and measure the level
of the carriers for every operator.
8. Set the adjustable attenuators in order to have the right level of the carriers at
the input of the TFL according to the technical specifications.