TV flyback transformers

[boylesg]

Why do the primary coils of these have polarity? Is it due to the presence of diodes in the primary circuit?

 

[FvM]

What do you mean with "coils have polarity"? In a transformer, you nee to know the relative direction of windings.

 

[boylesg]

What do you mean with "coils have polarity"? In a transformer, you nee to know the relative direction of windings.

Polarity as in which primary coil pin you connect the positive terminal to and which primary coil pin you connect the negative terminal to. They are supposed to generate a better secondary current with one polarity than the other way around.

 

[FvM]

Are you referring to a specific part? Today's TV flyback transformers have built-in rectifier cascades ("split diode transformers"), these have of course a defined polarity.

You should also consider, that the polarity of the HV winding can't be reversed, because only one end has high voltage isolation.
In so far the polarity of the HV winding is prescribing the polarity of the primary.

 

[boylesg]

Are you referring to a specific part? Today's TV flyback transformers have built-in rectifier cascades ("split diode transformers"), these have of course a defined polarity.

You should also consider, that the polarity of the HV winding can't be reversed, because only one end has high voltage isolation.
In so far the polarity of the HV winding is prescribing the polarity of the primary.

Yeah I am ware that the HV winding has diodes.

Oh wait a minute.

If there are diodes in the HV winding then I guess that alone would cause the primary winding to have polarity.