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Circular References


New member
I have some components moving position, in an assembly, after a regen. Checking further I see that they are a circular reference.

I'm not sure what this is. Trying to fix this issue, am I looking for external reference within the part, or am I thinking of 2 entirely different issures (Circular reference vs External reference) ?

I realize that an external reference is created in an assy, say inserting a hole in a part2 from an existing hole in part1, but do the circular references come from not later fixing the external references in part2?


New member

There are a number of possible reasons the models are moving in the assembly. I don't know the assembly config, so it's impossible to say without seeing the file. However, the circular ref needs to be addressed regardless of external refs. In other words, both can be mutually exclusive.

If you read the circ ref error text file it will tell you what the loop is. You may find it is something as simple as a reference placed while a part was in insert mode. Or, a Part1 hole ref'd to assembled component Part2 after the Part1 was placed.

The point...get rid of the circ ref...it can goof up important info.


New member
In your relationships:



Or, as mentioned above, one part references another part and vise versa.

laser guy

New member

I ususally open up sketch of the offending feature. Then I go to sketcher references and delete all the references but the primary datums (hopefully you are using the ones in the part and not in the assembly). Then redimension the sketch accordingly, complete the sketch, and regen. It works good and can reduce regen time in some cases.

To find what the circular referenced features are, open your working directory outside of PRO (like in windows explorer) and look for that part name with a crc extension: example.crc. This is a simple text file and will tell you how many times features are referencing themselves as well as exactly what the features are.

Once you think you have it fixed, delete the crc file, and regerate the part. If the file comes back you still have the circular reference(s).

-Good luck, they can be a pain sometimes, but I really recommend you get rid of them because they can cause problems later. Although I can't give specifics, they tend to be grimlins for me and just sit behind the scenes screwing with things.


try to check your model with the modelcheck module

there you will find explainations about your circular references



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