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In theory, you can. If you have a power transformer rated at 480 primary side and the secondary at say 120VAC, then the ratio is 4:1. Meaning that there are four times the number of turns on the primary side as to the secondary. So, if you were to power the primary side with 120VAC as opposed to 480VAC you would expect to see a 1/4 reduction in voltage output on the secondary, or 30VAC. The current would be dependant on the cross section of the secondary conductor and core construction. As current is increased thru the load (as in resistance welding) for example, you would expect voltage to decrease or lag, a larger Industrial sized transformer is able to compensate for this lag in voltage better than a compact household power transformer.

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Q: Can you use a 480VAC step down transformer and apply 120VAC to the primary?
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How emf induce while apply in primary side of the transformer?

when an alternating current apply on primary side of transformer then magnetic flux produced in the iron core of transformer.Then flux link with secondary winding of transformer so that an emf produced in a transformer.


Can one intentionally short ct to one side of transformer?

yes........ we can short circuit the other side of the winding wen the primary is excited.... but we shouldn't apply rated voltage to the primary.. this method is used in the short circuit test of the transformer to find the parameters of the transformer.....


How can you find primary from secondary coil?

Primary and secondary are only terms of convenience based on the ratings and purpose of the transformer. If a transformer is labeled 120 to 240 volts, just pick a winding and apply 120 VAC. If the output is 240 volts you found the primary and secondary. If you apply 120 volts and get 60 volts out that means the side where you applied 120 VAC is the secondary.


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.


What are the primary winding and secondary winding of a transformer?

The primary winding is the winding connected to the supply, while the secondary winding is the winding connected to the load. The terms, 'primary' and 'secondary' are unrelated to voltage levels.


Does the transformer require exactly 230V as an input supply else can we use 50V as the input for it?

You can apply a lower-than-rated voltage to the primary winding of a transformer, and the secondary winding will then alter by the same proportion. So, for example, for a step-down transformer, if a 230-V primary voltage results in, say, a 115-V secondary voltage, then applying a 50-V primary voltage will result in a 25-V secondary voltage.


How do you calculate transformer nubmber of turnes?

You need to apply the general voltage equation for a transformer. For the primary winding, this is:Ep = 4.44 Np f (flux)max... where Ep is the voltage induced into the primary winding, Np is the number of turns, and f is the supply frequency.The secondary turns can then be determined from the desired voltage ratio.


Can you use a step down transformer as a step up transformer by reversing the primary voltage as a secondary voltage?

If the transformer has two separate windings, then, YES a step-down can be used as a step-up, and vice-versa.It is more correct to say you are reversing the high and low sides.By definition Primary is the "IN" side and Secondary is the "OUT" side.The Primary could be the high voltage side if it is a step-down,or it could be the low voltage side, if it is a step-up.Design ConsiderationsCare must be taken when reversing the operation of a step-down transformer to insure that it does not exceed the ratings of the transformer. For example, let's say we have a 12 VA step-down transformer that takes 120Vac in and is rated to provide 12V at 1 amp at the secondary. If we were to reverse it and apply 12Vac to the new primary (the old secondary), we would have 120Vac at the new secondary, but to keep within the original ratings it could only be loaded to 0.1A @ 120Vac.As long as you treat the output rating of the step-down transformer as the input rating as a step-up transformer, and don't try to draw current beyond what would normally have been applied to the high voltage primary, you should be fine. Potentially one could push up the voltage on such a transformer beyond what its stated application specified, while making sure not to exceed the power rating of the transformer and not exceeding the breakdown voltage of the transformer's insulation, for example driving the above transformer at 24V to get 0.05A @ 240Vac. It is important to realize though that the rated input voltage for a step-down transformer will likely not be a safe input voltage if you use it as a step-up transformer - for example, applying 120V to the above transformer with the windings reversed would generate 1.2KV!One important point to remember when reversing a three-phase transformer to a step-up is what kind of windings it has. Most three-phase Transformers use a "delta" configuration on the primary side. This means that there are three "hot wires" and a ground, but not a neutral. (The white wire in a circuit). On the secondary side, transformers are usually wired up in a "Wye" (sometimes called a "star" configuration. Doing this allows the transformer to create a Neutral connection. If a step-down transformer is reversed to make it a step-up, the high (output) side will not have a Neutral connection. If one is not needed, say for a three-phase welding machine, this would not be a probem. However, if a Neutral IS needed ,say for lighting, reversing this transformer would not work. In this case, a listed step-up transformer will be needed. One final thing, if a step-down transformer is used as a step-up, a Neutral wire is not required to be connected to the input side.


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Voltage doesn't 'pass through' anything! Voltage is another word for 'potential difference', and is measured between two points in a circuit. For a transformer to work, it's necessary to apply an a.c. voltage across the transformer's primary terminals.


What happen if you apply triangular input to transformer?

there will be no neutral point in the circuit and high voltage will be across the transformer coils


What is the impedance of a transformer?

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.