Grid lines

Command : S3d_DrawGrid

When you click the Grid icon, the dialog with the grid options is displayed:

If you need to draw grids that are unequally spaced then you should enter in the Distance between grid lines field something like this for 4 grid lines : "5000 4000 6000"

When you click OK, the grid is drawn on the origin.
You can move/rotate/stretch these entities; these are regular lines that have their grid name attached to them.