Voltage divider in transformers?

[kevs926]

i never heard of such a thing but what could be the circuit analysis to this?

http://i.imgur.com/Zd6qn.jpg

what is V1 and V2?

what could make V1 and V2 not equal?

 

[Integral]

V1 and V2 would be voltages. The values of V1 and V2 will be determined by the properties of the coils shown.

 

[Studiot]

For a more complete answer you should post more details.

I can think of two practical situations you might be describing.

1) Transformers made for international markets sometimes have two primaries. The primaries are connected in series (as you have shown) for 200 - 250 volts and in parallel for 100 - 120 volt supplies.

2) Some circuits are sensitive to smaller variations in supply so the primary has taps or again there is a second primary with fewer turns. For 230 volt supplies the main primary only would be connected, for 215 volt supplies the second primary or tap would be added in series with the main.

In this case V₁ = 215 & V₂ = 15.

Hope this helps

go well

 

[kevs926]

V1 and V2 would be voltages. The values of V1 and V2 will be determined by the properties of the coils shown.

yeah this is what I am asking. what kind of properties would affect the voltage division on both transformers

for the example, how can you make 215 V1 and 15 V2? do i use 215turns on T1 and 15turns on T2? or do i use 2.15ohms internal resistance on V1 and 0.15 internal resistance on V2?

 

[vk6kro]

yeah this is what I am asking. what kind of properties would affect the voltage division on both transformers

for the example, how can you make 215 V1 and 15 V2? do i use 215turns on T1 and 15turns on T2? or do i use 2.15ohms internal resistance on V1 and 0.15 internal resistance on V2?

The voltages in a transformer are determined by the turns ratio of the windings.

So, if one winding has 100 turns and you apply 20 volts to it, then another winding that has 200 turns will produce 40 volts across it.
You can see that the voltage is related to the turns ratio.

Note, though, that the number of turns is not completely optional. If you had only had one turn and two turns, the transformer primary would not have enough inductance to limit the current drawn from the 20 volt supply.

As a rough guide, small power transformers need about 5 turns per volt. So, a 10 volt winding would need 50 turns.

If you have a transformer that is already constructed, you can put windings in series and the result will depend on the polarity of the windings. They may add to each other or they may subtract, depending on which way you connect them.