Please read Ideal Transformer and Practical Transformer before continuing. Consider a practical transformer on no load i.e., secondary on open-circuit as shown in figure below. The primary will draw a small current I0 to supply (i) the iron losses and (ii) a very small amount of copper loss in the primary. Hence the primary no load current … [Read more...] about Practical Transformer on No Load
Amazed why secondary of current transformer should not be open? If it is left open it may destroy the current transformer. So it is very important that the secondary of Current Transformer should not be kept open. The reason is quite interesting. Either it should be shorted or must be connected in series with a low resistance coil such as current coils of watt meter, coil of … [Read more...] about Why Current Transformer (CT) Seconday Should not be Open ?
Ideal Transformer An ideal transformer is one that has no winding resistance no leakage flux i.e., the same flux links both the windings no iron losses (i.e., eddy current and hysteresis losses) in the core Although an ideal transformer cannot be physically realized, yet its study provides a very powerful tool in the analysis of a practical transformer. In … [Read more...] about Ideal Transformer and Practical Transformer
Even though the basic functions of the oil used in transformers are heat conduction and electrical insulation, there are many other properties which make a particular oil eminently suitable. Properties of good transformer oil are explained in this article. Organic oils of vegetative or animal origin are good insulators but tend to decompose giving rise to acidic by-products … [Read more...] about Properties of Good Transformer Oil
What is the Percentage Impedance? The percentage impedance of a transformer is marked on most nameplates - but what is it and what does the Z% figure mean? The impedance of a transformer is the total opposition offered to alternating current. This may be calculated for each winding. However, a rather simple test provides a practical method of measuring the equivalent … [Read more...] about Percentage Impedance of Transformer and Its Calculation