question about multiple transformer wiring on primary side

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Everyone's different. From your question it seemed to me you didn't know how transformers work. I shall not make the mistake of helping you again. How you felt "insulted" by me posting a link is beyond me I'm afraid. I have not "trolled" you, but no problem I've been falsely accused before, as I said everyone's different, thank God.
 
What I don't understand for that arrangement is how current is flowing on the primary side of these transformers when current is drawn from the secondary side(s). Since the transformer primaries would be in series, current flow would be identical for both, but not necessarily the current draw from the secondaries. In fact, how does this even work for a single transformer of this type, where there are multiple secondaries which might draw vastly different current at any given time? This I cannot quite figure out in my mind, so I am looking for some background and info about it. Saying "dont' do that" is good, but I am always interested in WHY. I might, you know, learn something.

If I tell you that you have 230Vdc and two resistor (100 Ohm and 200 Ohm) connected in series to the 230Vdc, it is easy for you to tell me what is the voltage across each resistor. For 230Vac it is still easy. But, when you have transformers in-between each resistor and the 230Vac line, it seems at first very complicated.
With resistive loading of the transformers (secondary) it is still possible. A transformer acts as an impedance converter. As I recall, the impedance seen at the primary with a resistor connected at the secondary is the resistor value time the winding relationship squared. R x (Nprim/Nsec)squared. If you calculate the secondary resistance seen at the primary side, you end up with two resistor values on the primary side and can estimate how they divide the primary voltage.
Now to the worst - if the transformer secondaries are not connected to resistors but to complex impedance circuits like rectifier diodes and storage capacitors. Then you cannot calculate a corresponding primary impedance and the voltage split will vary with time.
 
I have some harvested amp boards and transformers that I would like to make use of. The transformers have a single 120VAC primary and multiple secondaries that are used to power multiple amp modules. ..... The question I have is how I might be able to use (or not) the same transformers on 220/230VAC mains (European standard). If I will be using two of these transformers, can I simply connect their primaries in series so that each one sees half the AC mains voltage? If I do that, can I leave some secondaries "unused" on one or both transformers?
Short answer NO, repeat NO.

As mentioned above, for each winding to get 1/2 mains, 110V each, you NEED to have **absolutely exact same consumption*** on both, which of course you can NOT guarantee at all, so answer is NO-

ONLY situation where that kludge might work would be if, say, 12V secondaries were wired in parallel, feeding a string of 12V quartz lamps, and IDENTICAL TRANSFORMER primaries were in series.

But that is not the use you intend, so NO.

Class AB (or even Class D) power amps are the most variable loads on Earth, go figure, because each microsecond current draw depends on signal input, which is constantly variable Music.

The lamp looad I suggested, by comparison, is steady and stable, and in any case, parallel load wiring ensure both secondaries get the same load, all the time.
Not your case.
 
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