INSUNITS return different values Civil 3D and AutoCAD?

[soonhui]

It seems like for this file, different people opening it on different machine will get different INSUNITS value.

For instance, I got 6 for INSUNITS, but another guy whom I sent the file to, got 4.

How can NSUNITS return different values for the same file? It appears that I'm using Civil 3D and he's using AutoCAD, see the next message in the thread. 

[soonhui · Accepted solution]

This is a further update.

It turns out that the discrepancy happens because I'm using Civil 3D and my colleague is using AutoCAD, so insunits return different values. And our experience is not unique, refer to this forum post INSUNITS Unitless is reset on open in Civil3D.

Woa! This creates a confusion that is of the highest degree.

The only conclusion I can draw from is that don't believe in insunits in Civil 3D. Which means if you open a DWG file in Civil 3D and it comes with a unit.. Civil 3D won't show it correctly. But if that's the case, how can I use Civil 3D if I can't even tell the unit?

[AllenJessup · Accepted solution]

My opinion is still the same as in 2018 Civil 3D tries to limit the units to Feet and Meters (poorly). There are many ways to change them, with consequences. 

As @cwr-pae mentioned. Adding INSUNITS to the acaddoc.lsp file will help. Also -SYNCINSUNITS will sync the INSUNITS with the Drawing Units.

[BrianHailey]

When I open the file in Civil 3D 2022, the INSUNITS is set to 0. Perhaps there is something in an acad.lsp file on your machines that is setting the units?

[rl_jackson]

When I open it, I get 6 (Meters), but its not a Autocad drawing, it's from some other software as I get the not a Autocad Drawing message.