I am trying to do a simple simulation of a plane wave incident on a PEC sphere. I am varying the radius of the sphere and grabbing the monostatic RCS to recreate figure 11-29 from Balanis Advanced E&M. I now want to look at how the induced surface current on the sphere changes as the sphere radius increases. I thought that I could do this using the Template based post-processing -> Evaluate field in arbitrary Coords. However, the plotted surface current doesn't match the surface current shown by the 2D/3D Results. Additionally, I get the following error when trying to plot the surface current while sweeping phi at theta = 90, this occurs when I check Select Solids, and then select the sphere component: 

Template based post-processing result "surface current (f=10) (pw)_Abs (Phi)":
Error in calling "Evaluate1D" function (Evaluate fields in arbitrary coordinates: Intersection between selected evaluation range and selected solid(s) is zero. Please check your settings.
(ReportError("Evaluate fields in arbitrary coordinates: Intersection between selected evaluation range and selected solid(s) is zero. Please check your settings."))(Line:2711))

Does anyone know how to resolve this error?

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