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Why load is always connected to secondary of transformer?
b'coz at the secondary side large amount of current flow by recarding of active component or other ckt. which is connected to the secondary side so that ckt. is not damage or burned by flowing large amount .. load is connected at the secondary side .AnswerThe 'primary' winding of a transformer is, by definition, whichever winding is connected to the supply, whereas the 'secondary' winding is whichever winding is connected to the load. This does not mean that a load MUST be connected to a transformer, as it will work 'off load' -that is, with no load connected- without any harm.
What is the voltage output if the transformer is connected backwards?
It doesn't really matter which way around you use a transformer, the primary winding is ALWAYS whichever winding you connect to the supply, and the secondary winding is ALWAYS whichever winding you connect to the load. For either connection, the turns ratio will ALWAYS equal the voltage ratio for an ideal transformer (or close enough for a real transformer).
Why power at the secondary winding is less than the power at the primary winding?
If power were greater at secondary you would have an unlimited source of power. It is less because there are always losses in a transformer.
When secondary coil is open there is no current in the primary coil WHY?
I am assuming the question is about the power / distribution transformer and not the current transformer. The primary current is a function of load connected on secondary. With the open secondary, there is no load, no current, it is open circuit. Hence no primary current. However there is always some small amount of no load current in the primary winding.
Why primary current is higher than secondary current in transformer with turns ratio 1?
In a transformer with a turns ratio equal to 1, the primary current comprises the reflected secondary current plus the magnetizing current necessary to sustain the "back EMF developed across the mutual inductance coupling the primary winding to the secondary. Therefore the primary current is always greater than the secondary current in a transformer with a turns ratio equal to 1. This should be evident by applying Kirchhoff's Current Law to the central node of the "T-equivalent" model of a transformer.
Why load is always connected to secondary of transformer?
b'coz at the secondary side large amount of current flow by recarding of active component or other ckt. which is connected to the secondary side so that ckt. is not damage or burned by flowing large amount .. load is connected at the secondary side .AnswerThe 'primary' winding of a transformer is, by definition, whichever winding is connected to the supply, whereas the 'secondary' winding is whichever winding is connected to the load. This does not mean that a load MUST be connected to a transformer, as it will work 'off load' -that is, with no load connected- without any harm.
What is the voltage output if the transformer is connected backwards?
It doesn't really matter which way around you use a transformer, the primary winding is ALWAYS whichever winding you connect to the supply, and the secondary winding is ALWAYS whichever winding you connect to the load. For either connection, the turns ratio will ALWAYS equal the voltage ratio for an ideal transformer (or close enough for a real transformer).
Why power at the secondary winding is less than the power at the primary winding?
If power were greater at secondary you would have an unlimited source of power. It is less because there are always losses in a transformer.
When secondary coil is open there is no current in the primary coil WHY?
I am assuming the question is about the power / distribution transformer and not the current transformer. The primary current is a function of load connected on secondary. With the open secondary, there is no load, no current, it is open circuit. Hence no primary current. However there is always some small amount of no load current in the primary winding.
Does the formula used to calculate the turns ratio uses the phase voltages and phase current?
No, the turns ratio formula calculates the ratio of the primary to secondary winding turns on a transformer using the number of turns on each winding. Phase voltages and currents are not directly used in this calculation.
Why primary current is higher than secondary current in transformer with turns ratio 1?
In a transformer with a turns ratio equal to 1, the primary current comprises the reflected secondary current plus the magnetizing current necessary to sustain the "back EMF developed across the mutual inductance coupling the primary winding to the secondary. Therefore the primary current is always greater than the secondary current in a transformer with a turns ratio equal to 1. This should be evident by applying Kirchhoff's Current Law to the central node of the "T-equivalent" model of a transformer.
What happens to the current as the voltage is increased by the step up transformer?
Compare a transformer to a balancing act. Both side need to remain equal.The primary side of the transformer is the supply side and the load is connected to the secondary side of the transformer.The load governs the current of the secondary side of the transformer and the voltage of the secondary side must match the voltage that the load required to operate.The ratio of the transformer will determine what the voltage of the secondary side is as compared to the voltage that has to be applied to the primary.The current of a step up transformer will be higher on the primary side that that of the secondary.Apply voltage and current to this concept and you will see that the transformer will remain balanced.The size of the transformer is always calculated from the secondary side of the transformer and the value is written in VA or KVA where V = voltage and A = amperage. Power factor is also taken into consideration when calculating the size of the transformer to be used.
How does a transformer work you mean how does it reduce current and increase the voltage you have tried the math this doesnt make any sense?
A transformer has a primary (Where the AC supply voltage is applied); and a secondary where a voltage is induced by a fluctuating magnetic field in the iron core of the transformer. The secondary voltage depends on the ratio of windings between the primary and secondary. Since the transformer can't manufacture power the product of the voltage and current at the primary exceeds that in the secondary. So if the transformer steps up the voltage in the secondary, the maximum current in the secondary must decrease. Similarly if the voltage is stepped down the maximum current increases in the secondary. There are always losses in this process so the power in is always somewhat less than power out.
Why generally the high voltage side of transformer is delta connected?
I don't know what kind of transformer you are talking about, but most utility distribution transformers are star connected on the primary side.AnswerIt might be different in some other countries, but in the UK, three-phase distribution transformers are always connected in delta on their primary (high voltage) side, and in star (wye) on the secondary (low voltage) side. The primary line voltage is 11 kV, while the secondary line/phase voltages are 400 V and 230 V.In the United States and Canada, the primary winding is also connected in delta -however, the secondary side is also connected in delta, with one phase centre- tapped to provide the split-phase 240/120 V arrangement.The reason for using a delta connection is because three-phase high-voltage lines are supplied as three line conductors -there is no provision for a neutral- so there is no practical advantage in having a star-connected primary.
WHAT STOPS a transformer windings FROM BEING A short circuit?
The transformer winding is a short circuit to DC. But for AC, the impedance of thecoiled winding and the magnetic coupling to another winding have the same effecton AC as resistance has in a DC circuit. That's why transformers don't work withDC, and are always operated with AC.AnswerIf you are querying why there are no short circuits between individual turns, it is because the windings are insulated not bare.
What is vector group YNd11 in transformer?
Vector group means it defines the primary & secondary side connection type of the transformer. It says D for the delta connections (windings connected between two phases) & Y for the star connections (windings connected from each phase to ground). The 11 stands for the phase displacement of the secondary referenced to the primary. Imagine a clock with only an hour hand; at 11 o'clock, the hand is at 30 degrees to the reference (12 c'clock), so the secondary is at 30 degrees to the primary.D or d means delta connectionY or y means star/wye connectionz means zed/zigzag/interconnected star connectionN or n means the Neutral point is accessible in the star connection. This is also sometimes taken to mean that the neutral point is earthed.A number means a phase shift in the secondary with respect to the primary, where the phase is measured in "hours"A capital letter indicates primary winding and lower case secondary. Capital z does not occur as zed transformers are used only for creating an earth on an unearthed system and thus are always on the earthed secondary.Primary is taken to be the higher voltage side, regardless of the direction of power flow.So, Dyn11 means delta primary, star secondary leading the primary by 30 degrees, possibly with an earthed neutral
What is the result when 3 kva power requirement is being supplied by 250 kva transformer?
The result is that the transformer runs cool and contented. The '250 KVA' rating on the transformer is its maximum ability to transfer power from its input to its output without overheating, NOT an amount of power always running through it. If the 3 KVA load happens to be the only thing connected to the transformer at the time, then only 3 KVA flows into the transformer from the primary line, and only 3 KVA leaves the transformer secondary.
