I have a selfbuilt ventilation system in my house, including a selfmade heat exchanger.

Of course I'm interesting to measure efficiency of the system, so I added temperature and humidity sensors to it and even realized a function that it only ventilates when the outside humidity is low enough to avoid condensation at cool walls.

But are the in- and outlet ventilators running at the same flowrate?
How big is the pressure drop of the piping and the corresponding reduced flowrate? Read More...

I read in a book about an effect called "dielectric absorption".
Basically it is an effect that each capacitor has. Depending on the dielectricum it is larger or smaller.

When a capacitor is discharged the capacitor charges up again after removing the shortcut between the 2 terminals.

Of course I had to test it myself :-)

My test setup:

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