Cable Testing / Locating

The T-906 is an easy to use, portable fault locator for low, medium and high-voltage power cables. It can be applied for the prelocation of all kinds of faults, including open circuit, short circuit, low resistance, high-resistance and flashovers. The T-906 can operate in four modes: Time Domain Reflectometry (TDR), Secondary/Multiple Impulse Method, (SIM/MIM), Decay Method and Impulse Current Method (ICM). Most power cable faults exhibit a high resistance, which requires the application of a high voltage surge to break it down for the purpose of pre-location. Of the four modes mentioned, ICM is the most cost-effective method of producing a flashover at the fault point using a standard surge generator. In the T-906, the ICM is augmented by an Automatic Impulse Current (AIC) method, in which waveform recognition techniques are applied to calculate the fault location automatically, without the need for the operator to manually interpret the waveforms. For flashover faults requiring a high breakdown voltage, the Decay Method can be applied in conjunction with a HV DC source. The cable is charged by the DC source until it breaks down, creating a transient voltage signal which is captured through a capacitive voltage divider and used for fault location analysis.