Fibre Optic Cable Types                                                                       << back to main technical page

Multimode
Multimode fibre carries multiple light rays or modes concurrently, each at a slightly different reflection angle within the fibre core. Multimode fibre has a larger core than single mode and is typically either 50µ (Micron) or 62.5µ (Micron) in diameter. Multimode fibre transmission is used for relatively short distances because the modes tend to disperse over longer lengths. The maximum distances of the cable depends on the application the cable is being used for. To run Gigabit over Multimode, a guideline of 550 Metres maximum for 50/125 cable and 220 Metres maximum for 62.5/125 cable should be used. For longer distances, Singlemode fibre is used. The most common application for Multimode is LAN's(Local Area Network).

Singlemode
Singlemode fibre is designed for the transmission of a single ray or mode of light as a carrier over long-distance signal transmission. Singlemode fibre has a much smaller core than multimode fibre, between 8µ and 10µ (micron). Singlemode cable can carry Gigabit upto 5,000 Metres. Singlemode provides greater bandwidth than multimode.

Loose Tube (L/T)
This is the protective tube surrounding one or more fibres and is usually found in cables used for outdoor installations. The protective tube loosely surrounds the optical fibre cores and is often filled with protective gel.

Tight Buffered
A protective coating (usually 900 µm) that is used to "buffer" the primary coating of fibres. Provides strength, durability, easy handling and termination.

Internal/External (Int/Ext)
Fibre Cable that is suitable for both indoor and outdoor applications. The cable construction usually uses a gel filled loose tube containing the fibres.

Armoured
The inner jacket of the cable is overlaid with a protective armouring. Two main types are Steel Wire Armoured (SWA) and Corrugated Steel Tape armoured (CST or STA). The armouring gives the best resistance against rodent attack or mechanical damage and provides high tensile strength and crush resistance.

LS0H/LSZH
Much of the cable currently in use in the world contains halogens. Halogens are gases such as fluorine, chlorine, iodine, or bromine. These halogens give off toxic fumes that harm the eyes, nose, lungs, and throat when exposed to flames. Many different manufacturers now make low-smoke, zero-halogen (LSZH or LS0H) cables that are designed to emit no toxic fumes and produce little or no smoke when exposed to flames. Many new buildings now specify this grade of cable to be installed.