The Megger ESG NT2 (1014430) Ground/Earth Fault Locator is used to accurately pinpoint cable sheath faults. This instrument comes with automatic calibration that keeps the display always at zero so users do not need to make any adjustments. The integrated noise suppression feature filters out all noise influences from DC, railway currents, industrial plants, and highly resistive soil environments. By using two earth rods, the ground step voltage potential can be measured and users can see the direction of the fault as indicated by the display. This instrument is ideal for use in the field due to the bright TFT color display that is able to be read in direct sunlight along with results being shown clearly as a bar graph. The ESG NT2 also comes with a history mode that allows users to view the deflections of the last 7 pulses.

Pinpointing means precisely locating faults in the cable sheath. These faults cause the measuring current to flow into the ground. When the measuring current exits the cable at the fault point, the current builds a voltage gradient which can be measured by earth rods and earth fault locators. The step voltage method accurately locates sheath faults where as it approaches the fault point, the step voltage potential increases. After it passes the fault, the potential decreases with reversed polarity. The change in polarity allows the fault to be located precisely.

The ESG NT2 Ground/Earth Fault Locator measures the step voltage potential produced by underground test generators. Other existing underground distortions such as potential equalization current, DC offset, 16 2/3 Hz or influences from cathodic protection systems are automatically detected and eliminated. The automatic zero calibration maintains the display calibration continuously at zero.

The ESG NT2 has a high-contrast color display on which the measured step voltage is displayed in two ways. These displays include as a bar graph that is similar to a conventional pointer instrument and as a continuous 'history-display' which shows both the current process and the last 5 to 6 measurement records. In this way, changes are displayed clearly and continuously.

The deflection of the instrument always indicates the direction of the earth fault. Due to the easyGO principle, almost no operational steps are required. Basic settings can be made simply by using the rotary encoder.

The ESG NT2 automatically adapts to the input voltage level. Neither manual calibration of the display and zero point, nor the adaption of the measuring range is necessary. Moreover, the ESG NT2 has an automatic pulse detector, allowing it to work with almost any type of pulse generator.

In addition to the standard pinpointing mode, the ESG NT2 also has a power frequency detection mode. In this mode, high-ohmic phase-to-ground faults on low voltage cables can easily be identified and pinpointed without the use of an additional signal generator. This is a useful time and cost-saving function especially helpful where house connection boxes are not accessible and the normal procedure would be cutting the cable.