Solar North how to use

Is there any written or video explanation on how to use Solar North plugin ?

It’s pretty basic. Click on the first button in the toolbar to show the orange line representing the Solar North angle. Choose the second button, click at some point in the model space (probably the origin) and drag out the solar north angle. Choose the third button and enter the solar north angle in degrees clockwise from default north which is along the solid green axis line when the axes are in their default position.

Thank you very much for your quick response !!
Do you mean that the second and third buttons are the same,
both of them define a new north direction,
and the only difference between them is that the second one is graphic north pointed,
while the third one is by degree numbers?

Yes but they do it in different ways. The second button lets you click some place and then drag out the north angle while the third one requires you to type in the angle. Try it. You can’t hurt anything.

OK ! Thounds very simple. I will give it a try. Thank you very much !!