Well I thought that you could tell me what is wrong, because the only thing I change is the voltage max (the step size changes automatically, I don't see why I should change the number of steps), but when I put Vmax = 10V one of the dimensions of the electric field disappears and looks like:
When actually it should look like this: 
So my question is, why it does so?
You are navigating away from the AIS Discovery experience