Fibre & Data Industries » Products & Services

Terminating/Splicing

Lynne Hutchinson — Sat, 11 Jul 2009 04:02:08 +0000

TERMINATING

We terminate fibre optic cable two ways – with connectors that can mate two fibres to create a temporary joint and/or connect the fibre to a piece of network gear, or with splices which create a permanent joint between the two fibres. These terminations must be of the right style, installed in a manner that makes them have little light loss, and protected against dirt or damage in use. No area of fibre optics is given greater attention than termination. Manufacturers have come up with over 80 styles of connectors and about a dozen ways to install them. There are two types of splices and many ways of implementing the splice. Fortunately for me and you, only a few of these types are used for most applications. Different connectors are used in singlemode and multimode terminations, so be sure of the type required before you order.

TERMINATION PROCEDURES

Connectors are usually installed on the cables after installing and are usually terminated by splicing a factory-made “pigtail” onto the Fibre. Cables can be pulled with connectors already on them if, and a big if, you can deal with these two problems: Firstly, the length must be precise. Too short and you have to pull another longer one (its often not cost effective to splice); too long and you waste money and have to store the extra cable length. Secondly, the connectors must be protected. Some cable and connector manufacturers offer protective sleeves to cover the connectors, but you must still be much more careful in pulling cables. You might consider terminating one end and pulling the unterminated end to not risk the connectors.

There is a growing movement to install preterminated systems with MPO multifibre connectors. These are tiny & shy; not much bigger than an ST or SC, but has up to 12 fibres. Manufactures sell multifibre cables with MPOs on them that connect to preterminated patch panels with SCs or LCs. These work well if you have a good designer and can live with the higher loss (~1 dB) typical of these connectors.

CONNECTOR AND SPLICE LOSS MECHANISMS

Connector and splice loss is caused by a number of factors. Loss is minimized when the two fibre cores are identical and perfectly aligned, the connectors or splices are properly finished and no dirt is present. Only the light that is coupled into the receiving fibre’s core will propagate, so all the rest of the light becomes the connector or splice loss.

End gaps cause two problems, insertion loss and return loss. The emerging cone of light from the connector will spill over the core of the receiving fibre and be lost. Connectors use a number of polishing techniques to ensure physical contact of the fibre ends to minimize back reflection. On mechanical splices, it is possible to reduce back reflection by using non-perpendicular cleaves, which cause back reflections to be absorbed in the cladding of the fibre.

The end finish of the fibre must be properly polished to minimize loss. A rough surface will scatter light and dirt can scatter and absorb light. Since the optical fibre is so small, typical airborne dirt can be a major source of loss. Whenever connectors are not terminated, they should be covered to protect the end of the ferrule from dirt. One should never touch the end of the ferrule, since the oils on your skin causes the fibre to attract dirt. Before connection and testing, it is necessary to clean connectors with a suitable cleaning device.

SPLICING

Splicing is a “permanent” connection between two fibre cores, and is the preferred method for terminating. There are two types of splices, fusion and mechanical.

Fusion Splices are made by “welding” the two fibers together by an electric arc. Field fusion splicing is usually done above ground in a truck or trailer set up for the purpose.
Mechanical Splices are alignment gadgets that hold the ends of two fibers together with some index matching gel or glue between them. There are a number of types of mechanical splices, like little glass tubes or V-shaped metal clamps.

Fibre Optic Repairs

Lynne Hutchinson — Fri, 10 Jul 2009 04:14:11 +0000

FDI offers a wide range of Repair Services and Programs for virtually any fibre optic product.

FDI’s Repair Service: from simple cleaning to re-termination, or in some cases re-building the entire product, depending on the nature of the product and the required finished performance. In offering these services, our goal is to help our customers leverage the investment they have made in their products by repairing them, rather than replacing them.

FDI’s Services are focused on examining, testing, and documenting products for physical and optical performance. As a part of this process, we can make repairs to the product to ensure it meets performance specifications once complete. This service is a preventative maintenance option we provide for our customers who want to ensure their products are performing at their best and want to make sure the opportunity for product failure during operation is at a minimum.

As part of our Repairs, FDI offers ongoing maintenance and programs catering to the needs of you specifically, should you want to take up a ‘Service Agreement’. Working with us to build a custom, regular maintenance program can be one of the most cost-effective ways to keep your fibre optic products in good operating condition, greatly reducing the opportunity for a product to fail during a critical operation.

Blown Fibre Installations

Lynne Hutchinson — Thu, 09 Jul 2009 04:11:54 +0000

Air-blown fibre is a method of installing fibre optic cables that relies on the flow of compressed air easing the fibre all the way to its destination up to 1km away.

It can be difficult to justify 24 fibres when only 8 are needed for immediate connection. With blown fibre systems, a low-cost microduct route is installed, and fibre only added as and when it is needed, creating a fibre-lean solution. This can reduce your initial costs & makes for a quick & easy upgrade in the future.

Testing & Auditing

Lynne Hutchinson — Wed, 08 Jul 2009 04:12:38 +0000

Testing

Our LAN testing service enables companies to determine whether they have the necessary infrastructure to support Gigabit Ethernet protocols.

Many organizations find out too late that their new high bandwidth protocols are severely affecting network performance. This can prove to be expensive unless the necessary tests are carried out prior to introducing large bandwidth traffic to the network. Find out now if your network has the capacity to cope.

FDI will fully test, document and provide detailed recommendations, saving you time, money and giving you peace of mind.

We use the latest fluke DTX cable analyzers to provide a Gigabit Ethernet cable testing service which enables companies to determine whether they have the necessary infrastructure to support Gigabit Ethernet protocols.

Cable Installation & Hauling

Lynne Hutchinson — Mon, 06 Jul 2009 04:14:58 +0000

Installation methods for both wire cables and optical fibre cables are similar. Fibre cable can be pulled with much greater force than copper wire if you pull it correctly. Just remember these rules:

Do not pull on the fibres, pull on the strength members only! The cable manufacturer gives you the perfect solution to pulling the cables, they install special strength members, usually duPont Kevlar aramid yarn or a fibreglass rod to pull on. Use it! Any other method may put stress on the fibres and harm them. Most cables cannot be pulled by the jacket. Do not pull on the jacket unless it is specifically approved by the cable manufacturers and you use an approved cable grip.

Do not exceed the maximum pulling load rating. On long runs, use proper lubricants and make sure they are compatible with the cable jacket. On really long runs, pull from the middle out to both ends. If possible, use an automated puller with tension control or at least a breakaway pulling eye.

Do not exceed the cable bend radius. Fibre is stronger than steel when you pull it straight, but it breaks easily when bent too tightly. These will harm the fibres, maybe immediately, maybe not for a few years, but you will harm them and the cable must be removed and thrown away!

Do not twist the cable. Putting a twist in the cable can stress the fibres too. Always roll the cable off the spool instead of spinning it off the spool end. This will put a twist in the cable for every turn on the spool! If you are laying cable out for a long pull, use a “figure 8″ on the ground to prevent twisting (the figure 8 puts a half twist in on one side of the 8 and takes it out on the other, preventing twists.) And always use a swivel pulling eye because pulling tension will cause twisting forces on the cable.

Check the length. Make sure the cable is long enough for the run. It’s not easy or cheap to splice fibre and it needs special protection. Try to make it in one pull, possible up to about 2-3 miles.

Conduit and Innerduct: Outside plant cables are either installed in conduit or innerduct or direct buried, depending on the cable type. Building cables can be installed directly, but you might consider putting them inside plenum-rated innerduct. This innerduct is bright orange and will provide a good way to identify fibre optic cable and protect it from damage, generally a result of someone cutting it by mistake! The innerduct can speed installation and maybe even cut costs. It can be installed quickly by unskilled labour, then the fibre cable can be pulled through in seconds. You can even get the innerduct with pulling tape already installed.

Long Haul Specialists

daniel — Sun, 05 Jul 2009 03:48:55 +0000

Here at Fibre & Data Industries, aswell as doing the small little jobs we can also run long haul cable for Mining, Gas and other industries that need fibre to be run for hundreds of kilometres. We have carried out various jobs like this in the past with great success and if you need cable to be run for your next multi mile project than look no further than Fibre & Data Industries.

Design & Consultation

Lynne Hutchinson — Fri, 03 Jul 2009 04:17:36 +0000

Here at FDI we can design your whole Fibre Optic System and using our simplistic but efficient consultation process we can work out what is the best solution for your business needs.

Where a cable route is too long for conventional cabling or in areas where high levels of interference are likely, we can design and install a Fibre Optic Link. This link can be as basic as a single Fibre Optic cable or a complete Fibre Optic Network. We can offer a wide range of Fibre Optic converters and multiplexers to handle Video, Data and Audio signals.

FDI staff are experienced in Fibre Optic system design and configuration using either Single-mode or Multi-mode fibres.

The design of the system will address all aspects including route planning and nodes, signal losses and the use of either internal or external cabling. The system will be configured to ensure that adequate bandwidth is available in relation to the application.

Our site based Engineering staff are also qualified in the installation and testing of complete Fibre Optic networks and are also fully trained to carry out splicing and jointing of Fibre Optic cables, using our own Fusion splicer.

Testing the Fibre Optic cable or network will be carried out by our own staff using either a multimode Fibre Optic light source and power meters or our own multi-mode OTDR test equipment.