High Voltage Test on Insulators: The High Voltage Test on Insulators that are normally conducted are usually subdivided as Type tests and The routine tests. Type tests are intended to prove or check the design…
Classification of High Voltage Testing Methods: Classification of High Voltage Testing Methods are divided into two groups: Power Frequency Withstand Voltage Impulse withstand voltage Tests These tests together ensure the over voltage withstand capability of…
Partial Discharge Measurements: Earlier the testing of insulators and other equipment was based on the insulation resistance measurements, dissipation factor measurements and breakdown tests. It was observed that the dissipation factor (tan δ) was voltage…
Schering Bridge Theory for Three Terminal Measurement: For two terminal measurements the bridge is grounded at its junction points. The supply transformer, detector, and all the components of the bridge are enclosed in earthed shields.…
Dissipation Factor in Schering Bridge: Extension of range of the Dissipation Factor in Schering Bridge can be achieved by connecting in parallel an additional large capacitance across C3. But to avoid expensive and large-size decade…
High Voltage Schering Bridge: In the power frequency range (25 to 100 Hz) High Voltage Schering Bridge is a very versatile and sensitive bridge and is readily suitable for high voltage measurements. The stress dependence…
Mole Bridge for Low Frequency Measurements: The bridge that is usually used for low frequency measurements is the Mole Bridge whose schematic diagram is shown in Fig. 9.10. This is primarily devised to measure the…
Dielectric Constant and Loss: Many insulating substances have dielectric constant greater than unity and have Dielectric Constant and Loss when subjected to a.c. voltages. These two quantities, namely, the dielectric constant and the loss depend…
Direct Current Resistivity Method: The specimen shape and the electrode arrangement should be such that the Direct Current Resistivity Method can be easily calculated. For a solid specimen, the preferable shape is a flat plate…
Insulation Coordination of Substation: For steep fronted lightning waves at Insulation Coordination of Substation and at different points on lines, the voltages at sub-stations may exceed the protective level depending on the distances involved and…
