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Let's look at a transformer first. Transformers are essentially two coils that are wrapped (wound) around a common core. The primary is supplied with a changing voltage. This develops a changing magnetic field in the core. And this changing magnetic field in the core "sweeps" the secondary windings and generates a voltage in those secondary windings. The changes in the primary due to the changing voltage are inductively coupled into the secondary to generate voltage there. The general answer to why a transformer doesn't work on a DC supply is that a DC voltage doesn't "change" and cause changes in the magnetic field in the core, and, thereby, cause changes in the voltage in the secondary windings. When we "turn on" the DC (direct current), a field will be built in the core, it will sweep the secondary windings and deliver a "pulse" as the field is built. But then the secondary voltage will drop to zero after the pulse. This is because there is a static magnetic field around the secondary windings, and a static field will not sweep the windings and generate a voltage. There will be no secondary voltage. It is possible to generate pulses of voltage in a transformer by pulsing a DC voltage supplied to the primary. The ignition coil in an automobile works in this way. The 12-volt supply is pulsed to the coil to generate the high voltage to fire the spark plugs. It is possible to get a transformer to work on DC. But, in general, transformers need a dynamically changing voltage supplied to them to cause the changing magnetic field in the core. This changing magnetic field will sweep the secondary windings and generate a changing voltage there. AC (alternating current) works really well for this application, and we use this idea in the power grids around the world.
A transformer works by induction. A magnetic field that builds up or collapses induces a current in a coil that is inside the field. For this you need the current that creates the field to turn of and on i.e. alternating current.
Direct current would create a static magnetic field and just one pulse of induced electricity in the secondary coil (at the moment the direct current was introduced to the primary coil) then nothing because the magnetic field would be constant.
This question, or one like it, continues to come up. Generally, the answer is no. If a transformer is hooked up to DC and turned on, the initial current flow induces a voltage in the secondary, but the voltage is gone in a moment. Then there's just "steady state" current in the primary and nothing in the secondary. Without a changing voltage (and the changing current) in the primary, there will be no changing magnet field, and it is the moving magnetic field, the "sweeping" of the magnetic lines of force across the secondary windings, that induces secondary voltage. No change in primary voltage (and current), no sweeping, no induced secondary voltage. But there are a lot of transformers that work on DC. It's just that the DC is turned on and off, or pulsed, to create the the "AC" to make the transformer work. The best example of this is the coil in a (non-diesel) motor vehicle. The 12 volts of the car's electrical system (it's actually a bit more) is "turned on and off" by the breaker points in the distributor, or by the ignition module in more modern cars. This pulses the primary of the ignition coil, and a huge secondary voltage - thousands of volts - is generated (and appropriately distributed) to cause the spark plugs to fire. There are a ton of pulsed DC transformers in wide application. All so-called switching or switched mode (pulse width modulated) power supplies (like the one in your PC) apply the idea of the pulsed DC drive on the primary of a transformer. Can DC operate a transformer? No. But pulsating or "switched" DC can.
Transformers require a changing current to create the changing electromagnetic field that makes them work the way they do. In DC circuits, there is no change, so there is no way for the transformer to create the field and transfer the energy.
Due to the DC current does not produce the induction in the primary of the transformer.
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If a dc voltage of 12v is added to the secondary of step down transformer and rating of transformer is 220 input and 12v output what will be the result from primary of transformer?
Adding a DC voltage to the secondary of a transformer will not have an effect on the primary side, as transformers work on the principle of electromagnetic induction which is based on alternating current. The primary side of the transformer will still operate based on the input AC voltage of 220V. The DC voltage on the secondary side will not be transferred to the primary side.
When transformer voltage regulation will be zero it operate at?
A transformer will operate with a voltage regulation of zero when it is not supplying a load.
What happens if dc supply is connected to incomer of transformer?
If a DC supply is connected to the incomer of a transformer, you effectively have a short circuit, because the DC impedance of a transformer (actually, any inductor) is quite low. You will blow something.
Why the windings burn when transformer is operated in DC?
Transformers are not intended to be operated in DC. DC does not provide the continuously fluctuating current that a transformer requires in order to function. On DC, a transformer will act as a transient mode inductor, and settle out to a high current state, destroying itself.
How dc supply is given to transformer used in push pull amplifiers?
The dc is supplied via a centre-tap on the transformer. This ensures zero dc net flux in the transformer core, which enables a much smaller core to be used.
Who will not operate on DC?
Transformer
Can transformer operate on triangular wave DC?
If its a triangular wave, its not DC, its AC, its just not sinusoidal. Can a transformer operate on triangular AC? Yes, but not as efficiently as on sinusoidal AC.
Why transformer do not operate with DC?
Transformer works with varying flux. DC won't create it. Only AC produce varying flux.
If DC is applied to the primary of a transformer is there any current in the secondary and if there is then whether ac or DC?
first, understand that a transformer is an AC DEVICE. it wont work on dc...
In D.C supply the transformer is not connected why?
In a DC power supply a transformer is connected. The only time there would be no transformer used would be if the DC voltage wanted was 120 VDC. The transformer in the power supply is connected to 120 VAC on the primary side and the secondary side of the transformer is connected to either a half wave or a full wave diode bridge. The voltage out of the diode bridge will be the same output voltage potential as the transformer's secondary voltage but it will be a DC (Direct Current) potential.Reading the question in another way, transformers are not connected in a DC circuit. The reason being is that the transformer operates on a collapsing magnetic field. This field induces a voltage into the secondary side of the transformer. Since the DC circuit does not operate on the principle of a collapsing field except when the circuit is opened, the transformer would not operate as a transformer should..
Why doesn't an AC appliance operate on DC?
Anything with a transformer in it will not work on DC because the transformer will draw enough current to blow the fuse (or catch fire) because transformers must always have a changing voltage. A simple heater will work on AC or DC. Appliances with most types of motor will only work on AC.
Why the winding resistance of transformer is not sufficent when it is used in dc supply?
It is.AnswerA transformer is designed to operate with an AC supply voltage, not DC -in fact, it cannot operate with a DC supply voltage.Opposition to the flow of alternating current is made up of resistance and reactance. Resistance depends upon the length, cross-sectional area, and resistivity of the transformer winding conductor. Reactance depends upon the inductance of the transformer winding and the frequency of the supply voltage.Because a transformer winding is highly inductive, its reactance is very much larger than its resistance, and is more than sufficient to limit the AC current to a value that will not overheat the winding conductor. However, if you supply the transformer with a DC voltage that is equivalent in value to its AC rated voltage, the low value of resistance will allow a very large DC current to flow -large enough, probably, to overheat the conductor insulation, possibly causing it to break down and cause severe damage to the transformer.
What is the DC output if DC input is used in an ac step up transformer?
The DC output will be zero because transformers do not operate on DC there would be a slight peak when switched but then it would settle to zero. Transformers require a changing magnetic field to transfer power.
When transformer voltage regulation will be zero it operate at?
A transformer will operate with a voltage regulation of zero when it is not supplying a load.
How does a DC transformer work?
transformer cannot be worked on DC because as the dc is constant there will be no change of flux & may lead to shot circuit.
Why will or won't a transformer operate on AC?
transformer will work on ac
How do you make ac into DC in a ac transformer?
You can not change AC into DC using a transformer. A transformer changes the voltage levels. To change AC into DC, you would need a rectifier. To change that into smooth DC you need a capaciter and a voltage regulater
