Swend
Full Member level 4
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- May 14, 2019
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Hi friends.
I have now two transformers which both suɔʞ at what they do, so I have named the left as "sucky-I" and the right as "sucky-II" (the black tape is self-vulcanizing rubber, excellent at keeping high pressure under control) , both have a turn ratio of about 10:1.
My premise is the one of the two transformers suɔʞ less than the other, so one will be better at transforming than the other, and that difference must visible in the measurements and give a hint of why the current on the secondary side more or less is the same as primary, but voltage gets stepped down alright.
This is the test environment for both transformers
This is "sucky-I"
x-axis is time in nano-seconds
This is "sucky-II"
x-axis is time in nano-seconds.
I guess the trace would be prettier with 30-40% less turns.
Where is the current? Current should go up when voltage is being stepped down.
Then I tried to separate the lower legs of each winding so that primary and secondary are galvaniacally separated, which meant I could only measure one side of the transformer at a time due to lack of diff-probe. But what happened was that then the current on the secondary decreased by more than 40%, now why is that?
Here are the scope traces for "sucky-I" (but the same happens for "sucky-II"), the white trace is ch2 integrated and is the actual current but you have to scale it with -3,552560e6 to get the correct magnitude. ch4 is the voltage which needs to be scaled by a factor of 100.
The integral scale is 5µV/DIV as can be seen in the text on the center axis.
The integral scale is 2.5µV/DIV as can be seen in the text on the center axis.
I have now two transformers which both suɔʞ at what they do, so I have named the left as "sucky-I" and the right as "sucky-II" (the black tape is self-vulcanizing rubber, excellent at keeping high pressure under control) , both have a turn ratio of about 10:1.
My premise is the one of the two transformers suɔʞ less than the other, so one will be better at transforming than the other, and that difference must visible in the measurements and give a hint of why the current on the secondary side more or less is the same as primary, but voltage gets stepped down alright.
This is the test environment for both transformers
This is "sucky-I"
x-axis is time in nano-seconds
This is "sucky-II"
x-axis is time in nano-seconds.
I guess the trace would be prettier with 30-40% less turns.
Where is the current? Current should go up when voltage is being stepped down.
Then I tried to separate the lower legs of each winding so that primary and secondary are galvaniacally separated, which meant I could only measure one side of the transformer at a time due to lack of diff-probe. But what happened was that then the current on the secondary decreased by more than 40%, now why is that?
Here are the scope traces for "sucky-I" (but the same happens for "sucky-II"), the white trace is ch2 integrated and is the actual current but you have to scale it with -3,552560e6 to get the correct magnitude. ch4 is the voltage which needs to be scaled by a factor of 100.
The integral scale is 5µV/DIV as can be seen in the text on the center axis.
The integral scale is 2.5µV/DIV as can be seen in the text on the center axis.