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PSU II Question

I'm a little puzzled about some of the results from PSU program.
For I1 I have 100mA stepped to 170mA (after 3 seconds). In the same way I have I2 4mA stepped into 8mA after 4 seconds.
When I ran the results after 20 seconds I see I1 = 100mA and I2 = 8mA. I don't think I1 should be 100mA but 170mA (especially after 20 seconds). To me the final currents should be 170mA and 8mA.
The current through the choke is 178mA (which is correct).

Am I doing something wrong here?

Second picture shows the transient time at the beginning of the simulation.

Thank you,


  • Psu 1.jpg
    Psu 1.jpg
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  • Psu 2.jpg
    Psu 2.jpg
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PSUDII and Current taps

I tried out this simulation and got the same results as everyone else ( no surprise there)
I fooled around a bit with adding more current taps and changing the timing etc and it looks like the only current tap that gets the correct current to plot is the one used as the final load. Any other position it behaves as L1 does in the original post. The simulations seem to be correct ie they draw the second requested current, just reporting the first one the plot.

I don't see a place to provide feed back on the DuncanAmps web page, or anything in the PSUDII help file, otherwise I would report this as a bug.
Hi all, I've tracked down the problem. The current tap placed in the middle somewhere would actually work correctly and step at the right time, it was just reporting all wrong.

This has now been fixed and a new version, 2.0.3 build 42 has been uploaded to the website. The download page is at Download

Please back up your rectifiers.txt file first if you have been making amendments to it as the installer will overwrite it.