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The secondary winding of a transformer consists of two windings in parallel, however they share the same core. They have the same number of turns, one cw the other ccw. Will the corresponding magnetic fields cancel each other out? enter image description here

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  • \$\begingroup\$ If you arranged that , you would get no voltage out. \$\endgroup\$
    – D.A.S.
    Commented Apr 29, 2022 at 5:35
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    \$\begingroup\$ This looks like a test question. \$\endgroup\$
    – Solar Mike
    Commented Apr 29, 2022 at 5:53
  • \$\begingroup\$ No matter how you arrange that , the result is 0V in series or parallel. with a short cct. and circulating currents. \$\endgroup\$
    – D.A.S.
    Commented Apr 29, 2022 at 10:30

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If you passed a current through a secondary which consisted of two half windings in either anti-series or anti-parallel, then the magnetic fields due to the currents would cancel out to zero.

You have specified secondaries though. Another way to look at it would be that the magnetic field in the core due to a primary excitation would create equal voltages in the two parts of the secondary. Let's call those voltages V. If they were in series, you'd get 2V out. If in parallel, you'd get just V. If they were in anti-series, you would get zero volts out because the two voltages oppose each other. If they were in anti-parallel, you would have short-circuited turns, and would get zero voltage out with a large current flowing, followed by smoke and fire.

Your drawing appears to show the two windings in parallel (I'm trying to infer the polarity of each winding from the representation of each solenoid, but I may be wrong), so you'll simply get the voltage V corresponding to one winding out.

When we draw transformers, we tend to specify that all windings are wound the same way round, then we specify the start of each winding with a dot. All dots then have the same polarity. This avoids the problems that you run into with your drawing method, trying to infer the polarity of the winding from the detail way you've drawn the winding. When draughtsmen of old drew transformers with a stencil, and the same thing tends to happen with CAD today, all windings are drawn the same, there's no information in the ambiguous perspective representation of a solenoid.

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  • \$\begingroup\$ I'm thinking the geometry is series but in actuality they are in parallel ie. the output is taken from one of the secondaries with the 2nd secondary sharing a common connection and the other end of the 2nd secondary joined to the other output connection.. \$\endgroup\$ Commented Apr 29, 2022 at 6:09
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    \$\begingroup\$ @user1897830 draw a diagram, put it in your original question, then we'll have another look \$\endgroup\$
    – Neil_UK
    Commented Apr 29, 2022 at 7:42
  • \$\begingroup\$ i'll see what I can do. \$\endgroup\$ Commented Apr 29, 2022 at 7:52
  • \$\begingroup\$ i.sstatic.net/iuW4C.png \$\endgroup\$
    – D.A.S.
    Commented Apr 29, 2022 at 12:18
  • \$\begingroup\$ @user1897830 updated my answer to address your diagram. \$\endgroup\$
    – Neil_UK
    Commented Apr 29, 2022 at 17:53

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