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Impedance (Z) voltage is the amount of voltage applied to the primary side to produce full load current in the secondary side. It is usually listed on the transformer nameplate, expressed as a percent, and measured by conducting a short circuit test.
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∙ 14y ago
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∙ 12y agoThe transformer impedance is the amount of voltage applied for transformer during the load test. the transformer primary voltage is 11000 v, secondary is 433. this transformer impedance is 5% take. this transformer HV side you apply only 550 v ,lv side short the all phases .you measuared the full load current .
AnswerThe term is a little misleading, as it describes a ratio of voltages, rather than an impedance. It's purpose is to assist in the process of fault levels calculations for the purpose of devising appropriate fault-protection settings.
The secondary winding of the transformer is short-circuited using an ammeter. The primary voltage is then gradually increased from zero until the rated secondary current is indicated on the meter. The primary voltage is then noted. The ratio of this primary voltage to its rated primary voltage, expressed as a percentage, is then termed the percentage impedance of the transformer.
For example, if a transformer's rated primary voltage is, say, 100 V, and an applied voltage of 15 V then causes the the rated secondary current to flow in the shorted secondary winding, then the percentage impedance would be [(15/100)x100]%, or 15%.
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How do you convert percent impedance of transformer to impedance value?
The apparent impedance looking into a transformer from one side will not be the same as looking in it from the other, which is why percent impedance is used. If you are looking from the high voltage winding (I'm labeling #1) to the low voltage winding (#2), you must scale the percent impedance as follows: (% impedance) x (Winding #1 nominal voltage)^2 / (transformer base VA)
What are the advantages of Transformer coupling method?
transformer coupling ensures maximum power transfer is obtained even if the output impedance is not equal to the load impedance
What is the effect of low impedance transformer on regulation?
The lower the impedance, the lower the voltage drop across the transformer as it is loaded. This means regulation is better, since voltage variance is smaller.
What is the relationship between frequency and the size of a transformer?
Basically the characteristics of a transformer depends on the impedance(resistance) and on the coupling of its primary and secondary coils. The impedance of a coil depends on the frequency, as the frequency increases you need less volume of iron core and less number of turns in the coil for a given impedance, then reducing the size of the transformer.
More the transformer impedance less the fault current... so is a high value of transformer impedance good for it?
It depends a lot on the application, i would go with low impedance transformers if am using the transformers for distribution as it will really increase the the maximum fault current. If am using the transformers as step up specially for generators or to charge capacitors, using a high impedance transformer is a good idea as it will decrease the inrush current of the system. you have to see your application and decide what fit that best. Mohammad Jaradat Power Generation Project Manager
How do you convert percent impedance of transformer to impedance value?
The apparent impedance looking into a transformer from one side will not be the same as looking in it from the other, which is why percent impedance is used. If you are looking from the high voltage winding (I'm labeling #1) to the low voltage winding (#2), you must scale the percent impedance as follows: (% impedance) x (Winding #1 nominal voltage)^2 / (transformer base VA)
What are the advantages of Transformer coupling method?
transformer coupling ensures maximum power transfer is obtained even if the output impedance is not equal to the load impedance
The purpose of transformer percentage impedance?
Inherently, the actual impedance seen at the secondary voltage will be different than that seen at the primary voltage. To make things easy, we use symmetrical components, where transformers are reduced to a p.u. (per unit) impedance. 100 x p.u. is equivalent to the percentage impedance you are referring to. When converted to per unit, a transformer has one impedance, not two, so it does not matter whether you are looking through the transformer from the secondary or the primary.
What is the effect of transformer impedance on regulation?
The lower the impedance, the lower the voltage drop across the transformer as it is loaded. This means regulation is better, since voltage variance is smaller.
How a transformer can be used as impedance matching?
If the line impedance is Z0 and the load is ZL then connect the load using a transformer with N turns ration. N=sqrt(Z0/ZL)
What is the effect of low impedance transformer on regulation?
The lower the impedance, the lower the voltage drop across the transformer as it is loaded. This means regulation is better, since voltage variance is smaller.
What is the relationship between frequency and the size of a transformer?
Basically the characteristics of a transformer depends on the impedance(resistance) and on the coupling of its primary and secondary coils. The impedance of a coil depends on the frequency, as the frequency increases you need less volume of iron core and less number of turns in the coil for a given impedance, then reducing the size of the transformer.
What type of transformer configuration will you select to design a high input impedance and low output impedance amplifier?
main volage
What is impedance of transformer?
The transformer impedance is the amount of voltage applied for transformer during the load test.Answer.I really don't agree with the answer given by the previous user.Impedance is the total vector opposition offered by the transformer to the flow of current i.e the vector sum of its pure resistance (R) and it's inductive reactance (XL). http://en.wikipedia.org/wiki/Electrical_impedanceAnother AnswerThe 'impedance' of a transformer is usually expressed as a 'percentage impedance', which is defined (perhaps rather confusingly!) as the ratio of the primary voltage that will result in the full rated current flowing through the secondary, to the rated primary voltage.
What are three requirement for connecting the transformer in paralle?
Transformer capacity (kvA) shall be identical, Both transformer impedance, secondary voltage and frequency shall be identical.
What is percentage impedance?
In electrical engineering, the percentage impedance of a transformer is the voltage drop on a full load, which is expressed as a percentage of the specified rated voltage. It's measured by conducting a short circuit test.
What is the difference between Ohm and Ohm CT in impedance of an audio transformer?
The side of the transformer that has the ohm CT which translates into a winding on the transformer that has a center tap . This side of the transformer was likely attached directly to the audio output transistors set up in push pull configuration. This is what the center tap is for. This side of the transformer would have a higher impedance and is directly driven by the power supply to provide amplification The transformer also isolates the amplifier voltage from the other side which is of low impedance. This may be in the range of 8 to to 16 ohms which would be directly tied to a speaker.
