Key Features:
- High surge energy up to 3500 J
- Fast surge rate
- Voltages between 2 and 32 kV
Together with reflectometers, surge generators are the central component of cable fault location. They are used for both pre-location and also pinpoint location.
Prelocation
Prelocation can be divided into transient methods and Arc reflection prelocation, which differentiates between passive, semi-active and active methods.
ICE – Impulse Current Method (ICE-Method = Impulse Current Equipment)
This method is particularly ideal for fault location in long ground cables and wet splices.
The surge wave generator ignites an arc at the fault. This results in a transient wave (i.e. a spreading and repeatedly reflected travelling wave) between the fault and the surge wave generator. An inductive coupler records this transient wave using the Teleflex reflectometer. The length of one full oscillation wave corresponds to the direct distance to the fault. A coupler for recording the transient current wave is fitted as a standard feature in all surge wave generators with a surge energy of 1000 J or more.
ARM – Arc Reflection Method (HV-supported reflection method)
All reflection prelocation methods offer the advantage of a very detailed measurement result. The result corresponds to the picture of a normal reflection measurement, making re-flection prelocation the preferred method for fault location. Differences occur with variations in technology, which can result in advantages such as a lighter system thanks to more simple structures being in place. More complex technologies are more efficient, but also have to be integrated into the wider measuring system.
The simplest method is the passive ARM method (previously called the arc stabilisation or short-term arc method). This extends the discharge of the surge generator and with it the burning duration of the arc by means of a series resistor in the discharge path.