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A transformer cannot do A. step up or step down a steady dc voltage b. step down ac voltage c couple power from primary to secondary d step up ac voltage?
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How calculate primary current in transformer the 50kva rating and 11kvprimary voltage?
The primary current is determined by the secondary current. So, if you don't know the secondary current, you cannot work out the primary current.If the secondary isn't connected to the load, then the primary current is simply the primary voltage divided by the impedance of the primary winding.You can, though, work out the 'rated' primary current (i.e. the value of current the primary can carry, continuously). For a single-phase transformer, this will be its rated apparent power (in volt amperes) divided by its rated primary voltage. So, in this particular case, we are looking at:rated primary current = (50 x 103) / (11 x 103) = 4.55 A
What is Primary Current?
Primary current is a flow to be measured that cannot be safely passed through the measuring device. A current transformer is used to provide a lower level, secondary current that can be passed safely through the measuring device. Primary current is measured as a secondary current, multiplied by the turns ratio in the current transformer.
What will happen to the transformer if rated voltage is applied to the winding during short circuit test?
If rated voltage is applied to Transformer during S/C test, The secondary winding will burn out due ta heavy current flow through the winding. During S/C test the secondary winding is short circuited so the impedance between phase and neutral is very low(only winding resistance). But the voltage across the secondary winding is rated hence heavy current flows through the winding, as I=V/Z. it depends which rated voltage is applied. if you are talking about primary winding voltage, transformer should withstand the primary rated voltage it's been designed for (OR it has been poorly designed). Otherwise, if rated voltage is the insulation voltage between a winding and earth OR winding-to-winding, you just have to check if: 1 - it is higher than the maximum primary winding voltage the transformer can withstand (could be, could not be..). Then, you can guess if your transformer is likely to burn or not. 2 - your test setup (usually a HV generator connected between primary and secondary winding) can deliver the requested current for the setup. I guess this won't be the case, since HV testers are usually designed to generate high voltages, but very small output currents.
What is the difference between Auto transformer and Power transformer?
An auto transformer has one winding with the output being tapped at some point and therefore has no isolation between primary and secondary. This may make it unsafe or illegal in some applications. A common power transformer has separate windings.
What is difference between transformer and power transformer?
In electricity supply systems, a 'power transformer' is a category of step-up or step-down transformer used in the high-voltage transmission and primary distribution systems. Step-down transformers used in the secondary distribution system are called 'distribution transformers'. A power transformer is designed to handle large amounts of power (as the name implies) and usually converts voltages; they are used in power supplies and in electrical supply. Transformers have three main functions in electronics; impedance conversion, voltage conversion and isolation. Because of these three applications, there are specialist types of transformers. For example, signal transformers are designed to match impedances - for example, between a record cartridge and an amplifier.
How much is the secondry voltage vs with a primary voltage is vp equals 120v?
As far as a transformer is concerned, the secondary voltage Vs value cannot be determined by the primary voltage Vp alone. For the simplest of calculations the transformer primary-secondary turn ratio must be known. For an ideal transformer ( and practicaly ideal transformers don't exist as there will be various losses in the transformer cores and windings), the simple equation relating secondary voltage to primary voltage would be : Vs/Vp=Ns/Np=Ip/Is where Ns is the number of winding turns in the secondary of the transformer, and Np the primary. Ip is the primary current and Is the secondary.
What is the voltage of the secondary coil when the primary coil is 1200 volts?
You cannot determine the voltage induced into the secondary winding of a transformer unless you know its turns ratio. In other words, you haven't supplied sufficient information to answer the question.
What happens when load is given to primary side of a transformer?
The Load will consume part of the power and therefore reduce the current (voltage ) available for the secondary part of the transformerAnswerYou cannot apply a load to the primary of a transformer which, by definition, is the winding connected to the supply voltage. Your question makes no sense.
Why can a CT be shorted and a Pt cannot?
A current transformer pushes a ratio of primary current in the secondary. A potential transformer pushes a ratio of primary voltage in the secondary. Shorting a CT allows the full current the CT wants to push to flow. Shorting a PT makes it very difficult for the PT to produce rated voltage. To keep the voltage at rated value, the PT would have to push ~infinite secondary current.
Why do a Voltage transformer give me a CLIPPED output signal?
Because the voltage on the primary winding is too high and the core gets saturated. When this happens the transformer effect cannot kep increasing the voltage on the secondary winding, clipping the output. Either reduce the voltage on the primary of get a oriented iron core with at least 10,000 gauss flux capacity.
Can a transformer step up power?
It is a basic tenet of physics that, in a closed system, energy can neither be created nor destroyed. Energy can, however, be transformed. It follows from this that the power output from a system cannot exceed the power input. Therefore, in a transformer, the primary power and the secondary power are always equal (at least in theory). A transformer can step voltage up or step it down. Since power equals voltage multiplied by current then, if the transformer secondary voltage is stepped up, the current must be stepped down by the same factor (that is, if the voltage is stepped up by a factor of 4 then the current is stepped down by a factor of 4). Any increase in voltage in the secondary of a transformer will result in a corresponding inversely proportional decrease in secondary current. From a practical standpoint, secondary power is always somewhat less than primary power due to resistive losses in the transformer windings as well as eddy current and hysteresis losses (magnetic losses) in the transformer core. These losses produce heat which compounds the transformer inefficiency. The primary and secondary windings are made from copper and, like all metals, it has a positive temperature coefficient of resistance. This is a fancy way of saying that when the copper windings of a transformer get hotter their electrical resistance goes up which further increases the resistive losses in the transformer.
How calculate primary current in transformer the 50kva rating and 11kvprimary voltage?
The primary current is determined by the secondary current. So, if you don't know the secondary current, you cannot work out the primary current.If the secondary isn't connected to the load, then the primary current is simply the primary voltage divided by the impedance of the primary winding.You can, though, work out the 'rated' primary current (i.e. the value of current the primary can carry, continuously). For a single-phase transformer, this will be its rated apparent power (in volt amperes) divided by its rated primary voltage. So, in this particular case, we are looking at:rated primary current = (50 x 103) / (11 x 103) = 4.55 A
What is current voltage transformer?
A transformer is a device that steps up, or steps down voltage. During this process current is also stepped up or down:however, voltage and current are inversely proportional ( meaning an increase in voltage results in a decrease in current and vice versa ) As an example: A step up transformer of 10:1 ratio with 12 volts and 10 amper of current applied to the primary will have ten times the voltage ( 120 volts ) and ten times less current ( 1 amrere ) at the secondary...and a step down transformer with the same turns ratio with 120 volts and 1 ampere applied to the primary will have 12 volts and ten ampere available at the secondary. The electricity supplied into homes and business uses wires carrying very high voltage and low current over long distances, then uses step down transformers to step down the voltage and step up the current. However, in power engineering and protective relaying applications, there are what are called "instrument transformers" which have the specific purpose of providing information to devices (such as relays or meters) about the voltages or currents in the power system. Therefore, there are some differences in construction and connectivity between a Current Transformer (CT) and a Voltage (or Potential) Transformer (PT). A CT will typically have a toroidal core and evenly distributed secondary windings so as to minimize leakage reactance. The primary is typically the main power line conductor, which passes directly through the toroidal core. This type of transformer is specifically for the purpose of measuring current values, and the secondary windings cannot be left open-circuited, or a large voltage will be produce, resulting in dielectric failure (and often an explosion). If a device is not connected to the CT, its secondary must be short-circuited. A PT is connected between the main conductor and ground and can be either wound in the normal way, or the voltage can be taken from a subsection of a string of capacitors (this is called a Capacitive Voltage Tansformer or CVT, and is usually cheaper than the wound type, but is typically not as accurate). This type of transformer measures voltage values, and the secondary winding cannot be short-circuited, as this will produce excessively high currents, resulting in the failure of the PT or the wires it is connected to. A PT can be left open-circuited.
What is the current carrying of an 1000kVA transformer?
You cannot answer this question without knowing the rated secondary voltage. Once you know this, divided the voltage into the volt ampere rating.
What transformer is needed to convert 220volts to 110 volts?
Yes, transformers which operate on 110 - 120 Volts exist. This question is probably incomplete as it only mentions one voltage: it could be for the primary or the secondary or for a single-winding auto-transformer. The missing information cannot be guessed...
How can you use step down transformer of 240 v ac to 24 v dc as step up transformer?
A step down transformer has a higher voltage (in this case 240v) primary and a lower voltage (in this case 24v) secondary. A step up transformer has a lower voltage primary and higher voltage secondary. In reality the transformer doesn't care which is which, so if you wire the 24v side as the primary and the 240v side as the secondary, you have a step up transformer. You might want to stick a fan on it to be sure it doesn't overheat, but that's all you need do.AnswerFrom your question, it sounds as though you are describing a power supply, rather than a transformer, as you specify the output is 24-V d.c. (direct current). Unfortunately, you cannot apply 24-V d.c. to the output side of a power supply, in order to obtain a 240-V a.c. output at the input side! This is because a power supply consists of a transformer to step down the a.c. voltage, and a rectifier (and, possibly, a smoothing filter) to produce a d.c. output. Applying d.c. to the input of a rectifier will not produce the a.c. necessary to run your transformer in the opposite direction!
What is Primary Current?
Primary current is a flow to be measured that cannot be safely passed through the measuring device. A current transformer is used to provide a lower level, secondary current that can be passed safely through the measuring device. Primary current is measured as a secondary current, multiplied by the turns ratio in the current transformer.
