This is a gripe/feature request more than a question.
I'm designing a spiral staircase, and at the bottom of the stairs the curve goes nearly straight. Of course nearly straight implies a curve with very high radius, in this case 62 000mm. The resulting helix requires a Height of 1284mm and Revolutions - 0.00626. That means the implied Pitch is ~205,000mm. The problem is the Helix feature seems to max out the Pitch at 200,000mm. When I created the feature it automatically reduced my Height to 1252mm (without alerting me) and after I discovered the problem and tried to correct that value, it immediately changes the value back to 1252.
In this case I am only slightly above the limit, so I can tweak my design a small amount so that my pitch is less than 200,000.
Still, why should there be a limit? Seems like an arbitrary and unnecessary limitation on design freedom. Why not 500,000? Are we running out of numbers after 200,000?
I don't know why there would be a limit of 200,000 mm for the pitch of a helix, but there are some hard and fast limits on the size of SolidWorks objects and perhaps this is somehow tied in with that. The basic rule is that eveything must fit within a 1 km cube centered on the origin, so nothing can lie outside of 500,000 mm in x, y or z.