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Fibre Cable Repair Options

One of the advantages of fibre optic cabling is its ability to be joined several times in the same installation run. This is also helpful if you are in need of a fibre cable repair

Of course it is best if the joint or as the industry refers to them “Splice Points” are pre-determined.

In many installations a fibre cable will be taken to a demarcation point and left coiled for future installation by others. The future installation then involves installing an additional fibre cable and splicing to the existing fibre creating a singular fibre connection cable.

Can Fibre Optic Cable be repaired?

Demarcation and splice points are a regular part of any fibre optic cabling installation. However incidents sometimes occur and call for a broken fibre cable to be repaired and joined to re-connect communication.

The investigation into whether the fibre cable is ok to be repaired depends on how it has come to be broken and how much slack (spare cable) is on the existing link.

How do you fix a broke fibre cable?

Fibre Cable Repair One

In the event that there is plenty of spare cable the two parts of the broken fibre can have the damaged ends cut off and prepared. These ends are then spliced together and secured in a protection box which houses the fibre optic cabling connectors.

Fibre Cable Repair Two

Should the link cable have additional damage or not have any spare slack then a different repair can be undertaken. In this situation the end are cut back to where the damaged has occurred on each damage point. Then to reconnect the link a new piece of fibre cable is inserted between the two points and spliced twice. Once to each end to again reconnect the communication link.

How are Fiber Optic Cables spliced together?

There are a few different ways to terminate fibre cables but by far the most common and professional is to use a fibre optic splicing machine.

Both ends of the cable are prepared and stripped back to exposure the glass core within the outer sheathing. Then the ends are cleaned and cut / cleaved to create a perfectly sharp straight end. Furthermore these ends are then placed into a plastic termination protector and lightly pushed together

Once inside the protector the tube is placed into a fibre splicing machine and the two glass ends are fused together to in essence create a single piece of glass tube. Therefore creating a new continuous fibre core for communication.

Locating breaks in fibre optic cabling

The outline above of repairing fibre cables is all well and good when you know where the break and damage has been done.

However when you lose connection on one of your links the process of finding that damaged area can seem impossible

However with a tester called an OTDR these faults can be found very accurately

OTDR – Optical Time Domain Reflectometer

What is the OTDR used for?

The unit is used for not only fault finding but also to test overall fibre link installation

The unit’s main uses are for

  1. Measuring the length of the installed fibre cable
  2. Calculating the overall loss along the fibre cable
  3. Highlighting the loss calculations of each event along the link which is mainly joints /splices. These also include the ultimate end termination points
  4. Fault finding

The unit works on the reflection of lights back along the length of the cable once the light is launched into the cable from one end. As the light hits certain points of the cable spikes are showed where the light is reflected. Small reflections shown for natural bends and parts of the cable. Larger spikes are seen at the start and end of the cable as the light hits the termination points. Furthermore these spikes will be seen for splice points along the cable.

Each of these spikes is in essence loss of signal along the cable

An in depth study into OTDR testing can be found on the FOA Website

OTDR and locating breaks in fibre optic cabling

The OTDR will measure the distance to a major event and show it on the light trace. When a cable is broken it shows a certain event on the OTDR trace. The fibre optic cabling installer can then move the cursor to the event of the broken cable and the unit calculates how far it from the start of the cable. In addition the test can be done again from the other end and get another distance to the break.

With these two distances it can be accurately estimated where the break in the cable is so it can be found.


Fiber optic cable repair cost

How much does it cost to repair fibre optic cable?

The cost will depends on many factors but as an outline our professional fibre optic cabling installers with fusion splicing and OTDR testers are £350-£450.00 per day

The factors that will affect the price to a lower or higher range are as follows

  • Type of cable and damaged

The majority of fibre cables are similar in price for a like for like cable. However fibre cables can range from 4 core cables (4 core connections inside the outer sheath) up to 96 cores and beyond

When a cable gets broken each core has to be repaired and spliced. Not only do higher core count cables have more termination repairs they are also harder to handle and therefore more time consuming

  • Location of the damage

The access and environment of the damage will make a difference in cost. Splicing a cable inside an office will of course be more cost effective than if its external, buried, or required high access outside of a building. However all are possible and can be communicated upon an onsite of offsite survey

  • Length of the fibre

A longer link will results in greater time to access both ends to firstly test to fault find and then to test to confirm repair. Fibre cables that are damaged between building naturally take longer to repairs than repairing a cable inside the same building

Emergency Fibre Repair Call Outs

The majority of fibre optic repairs can be repaired between 2-4 hours once attending the location. This will depend on factors such as those as above.

If your fibre cable is broken or you are having faults on your fibre cabling links call 0207 269 4717 or email [email protected]

For an explanation on what is optic cable and how does it work click HERE


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