ABB AC 800F

4 Cabling the AC 800F
4-43
4.2.10.3 Long-distance links within buildings
The fiber optic 10BaseFL cables described in the examples above are two-wire,
ready-made cables with BFOC connectors. They are designed for dry indoor
applications. The maximum possible length of a ready-made cable is 100 m.
Longer fiber optic cables first have to be to laid without connectors to avoid the risk of
fiber breaks. In a second operation so-called pig-tails are welded (spliced) to the fiber
optic cables. Pig-tails are short fiber optic cables of around 10 m with a connector
plug mounted to one end. The splice points are protected by splice boxes, which are
available for wall mounting or ceiling suspension.
Figure 4-24 shows the basic structure of a point-to-point connection with two splice
boxes.
Fig. 4-24 Point-to-point connection with splice boxes
Note that the fiber optic cables are normally available in a maximum length of 2000 m.
For longer distances an additional splice box for connecting the middle pieces or an
overlength cable is required.
Splicing is a welding operation which must be carried out by qualified personnel, only.
Contact the ABB service for splicing works. Splicing pig-tails is easier than mounting
connectors to the middle piece on site. Therefore, splicing should be preferred. Make
sure that the splice points meet the quality requirements by measuring/testing the
whole link on site and noting down the results in an acceptance record.
Pig-tails can be produced by cutting a ready-made 10BaseFL cable in two pieces.
Pig-tails should have a maximum length of 6 ... 10 m to enable easy measurement.
The surplus length, if existing, can be wound up in the splice box.