Getting To the heart of your telephone or broadband physical line fault or more to the point the actual cause of service performance issues. Line faults are often not visible to the naked eye, irrespective of routing (buried underground, pole span, attached to a property). There is a simple way to identify both the type of fault & a relatively accurate distance to the fault itself.
The technique is called Time Domain Reflectometry, simply put it is a method of measuring a known quantifiable electrical signal as it travels along a cable. This technique has been around for quite some time & has been widely used by the likes of BT Openreach to help maintain the cables on its network.
As the cost of this type of testing equipment comes down & the availability goes up it becomes a simple matter of technical training to fully understand how TDRs can be effective in helping to quickly resolve communication line faults. Additionally, this type of test equipment has become much more user-friendly & easier to use. Rather than having to understand the output of a signal trace on a time-relative graph, it is possible to buy TDR units that offer simple test routines, with results output using simple technical terminology.
In the early years, a technician would have to undergo comprehensive training to fully understand the principles behind deciphering graphs like the ones shown below.
High resistance joint
Lateral also some times referred to as a Bridge Tap
Open circuit
Short circuit
The cost of portable TDR technology has come down significantly. As such faults on your supply network are relatively easy to find, but, the cost implications of quickly rectifying all of them often present some commercial issues.
Burytec can help, if you need to locate a fault on a communications cable. Burytec can help you through the whole process. TDR testing works on both internal & external cables & can help identify distance to fault information.
A TDR can help diagnose many more types of line conditions than shown in the traces above, so if you want to get more technical & understand some of the additional features TDR technology has to offer, a good start would be to do some online searching for the following terms:-
- Pulse
- Impedance miss match
- Velocity of Propagation
- Spread Spectrum Time Domain Reflectometry
If you need help locating the distance to a fault on your cable in the North Manchester, Bury, Bolton or Rochdale areas contact Burytec.