Install Manual

BRITECELL System Manual MN010-04 June 2003 Page 63 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.
For in-building applications the most common fibre cables are tight buffered cables
with 2 fibres; examples are:
Duplex zip-cord: two simplex units in a zip cord configuration.
External
Dimension
(mm)
Maximum
Tension
(kg)
Weight
(kg/km)
Minimum Bend
Radius (mm)
2.5 x 5.3 30 11 30 (minor axis)
Duplex breakout cable: two individually coloured simplex units over sheathed in
a “figure 0” configuration.
External
Dimension
(mm)
Maximum
Tension
(kg)
Weight
(kg/km)
Minimum Bend
Radius (mm)
3.6 x 6 30 24 35 (minor axis)
Duplex light duty wiring cable: two individually coloured tight buffered fibres
surrounded by yarn annulus with a polymer over sheath.
External
Dimension
(mm)
Maximum
Tension
(kg)
Weight
(kg/km)
Minimum Bend
Radius (mm)
5 81 19 40
The main differences between these cables concern the maximum tension that
they can bear; this is an important characteristic to consider as, during laying,
installers often have to pull and to drag cables. For this reason the duplex light-
duty wiring cable is preferred, which is light and allows a tight band radius.
58.3.1. Connecting TFL and TFA with optical cables
A couple of fibre optics connects every Remote Unit with a TFL. It is very
important to well organise the layout of cables in order to avoid mistakes in the
connection (correspondence between a certain remote unit and a TFL).
Furthermore, a well-organised layout, allows good maintenance and
troubleshooting.
Every fibre must be labelled in order to understand which is the correspondence
between TFL port and Remote Unit.
During the connection of the pigtails to the TFL, some rules must be followed.
9
The pigtail cannot be squeezed or on traction and the minimum bend radius
suggested is 4 cm.
9
Don’t touch the fibre optic head of the optical connector
9
If necessary, clean the connector head by means of alcohol and proper paper
9
Use dry air spray to clean the TFL optical connector. Firstly spray to another
direction and then inside the connector as often some water can be on the first
spray.
9
Do not use other methods behind these to clean the optical connectors.