Cables are frequently used for the distribution of the electrical energy. Although the cables are highly developed, there are sometimes malfunctions in the cable system. Electric utilities often face the problem of finding the exact location of a failure in a distribution cable. These failures often occur at the worst possible time and cause the maximum amount of inconvenience to utility customers. The utility must quickly find and isolate the failure to restore electric service. Available fault locating methods use cable fault locator, “thumper,” radar, acoustic detector or combinations of these.
Fault locators are used to pinpoint faults occurring in communication / control cables to facilitate quick repair. In order to reduce down-time and facilitate easy maintenance, cable fault locators are indispensable. They use the principle of pulse reflection technique to quickly locate the point of occurrence of a fault, and are thus very flexible and time saving in nature. The demand for the product is bound to increase considering the growth of the telecom sector and cable operators in the entertainment sector in cities, metros and urban areas.
Cable faults are damage to cables which effect a resistance in the cable. If allowed to persist, this can lead to a voltage breakdown. The equipment user must use a quickest most efficient method of pin pointing an underground cable fault with minimal training required for use of the cable fault locator equipment. The manufacturer must design the equipment with easy operating features for quick precise pinpointing of a cable fault that minimizes any additional damage to the cable under test.
There are different types of cable faults, which must first be classified before they can be located. To locate a fault in the cable, the cable must first be tested for faults. Cable testing is therefore usually performed first in cable fault location. During the cable test, flash-overs are generated at the weak points in the cable, which can then be localised.
The measures necessary for determining fault locations can be subdivided into individual steps.
Insulation and resistance measurement provides information on the fault characteristics. An insulation test measures the insulation resistance between conductor and screen; from the periodic measurement of resistance you can derive the absorption properties of the insulating material.
In cable identification, the faulty cables are identified from the fault-free cables at the already determined site.
After the cable fault is identified and located, it is then possible to “burn it in” using burner devices, in other words to convert it from a low-resistive to a high-impedance fault.
To answer the need for gentler fault locating methods, the industry has developed more sophisticated methods that reduce the stress on aged insulation systems. The general approach is to reduce the amount of thumping necessary to locate a fault while simultaneously reducing the voltages required to perform the task.
Fiberstore offers a full range of fiber testers to choose from with the most efficient up to date TDR method coupled with our high voltage capacitive discharge units. Our line of cable fault locator and fiber visual fault locator is designed and manufactured based upon our hands on fault locating field expertise.