Voltage drop over 330 Ohm was 8.6V Therefore the current was 26.6mA. Voltage drop accross the transformer secondary was 22mV.
So around 0.8R is the secondary winding.
So around 0.8R is the secondary winding.
For some OTL power supply transformers it was better to wind the secondary winding first and the primary over the secondary to get lower dc values on the secondary winding. This could be done also on output transformers if they are wound in this way.
Wouldn't this increase the primary copper loss the same way as the secondary's is decreased?
Best regards!
Best regards!
No, as the primary winding is loaded with a high impedant source anyway it will be a few Ohms higher but the secondary will benifit from even half an Ohm less.
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Not the exact point. But two other points:
1. When you interleave an audio transformer, the MLT (Mean turn length) is distributed across the primary and secondary. In a few words, they share the same Rdc fate.
2. The transformer working as a whole, its losses depend of the whole primary and secondary combined. So if you put a primary as lowest layer, an upper secondary layer will suffer.
There are other reasons that make sense to do it when it comes to power transformer - optimizing losses per surface area for example, tweaking with the wires you have in stock. It makes to place the more lossy layers at the bottom to compensate. In some applications, it also makes sense to place the secondary first, if primary wire is fragile and needs to be protected from thick wire secondary pressure. In power transformers, one studies transformer cooling carefully as well.
1. When you interleave an audio transformer, the MLT (Mean turn length) is distributed across the primary and secondary. In a few words, they share the same Rdc fate.
2. The transformer working as a whole, its losses depend of the whole primary and secondary combined. So if you put a primary as lowest layer, an upper secondary layer will suffer.
There are other reasons that make sense to do it when it comes to power transformer - optimizing losses per surface area for example, tweaking with the wires you have in stock. It makes to place the more lossy layers at the bottom to compensate. In some applications, it also makes sense to place the secondary first, if primary wire is fragile and needs to be protected from thick wire secondary pressure. In power transformers, one studies transformer cooling carefully as well.
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