Assuming your text STYLES and DIMSTYLES are oth annotative, and your DIMSTYLE is using your annotative text STYLE, simply changing the viewport's scale will do it. If not you got something set incorrectly and you need to post a sample DWG file for others to help further.
Many thanks for your response. I'm sure that I am missing something here. Please see attached file. Square is 500 x 500 units and there are 2 annotative dimensions 1:5 on the top and 1:10 at the bottom of the square.
Viewport scales are set to 1:5 and 1:10.
Hope you can help.
I got the same results with your file. But I made it work once I did the following:
Deleted the viewports and dimensions in model space;
Reset the ANNOAUTOSCALE system variable to 0 (it was set to -4);
Redo the dimensions at 1:5 and 1:10 in model space; and,
Rebuild the viewports.
Simply resetting the system variable didn't do it by itself for some reason. I'm sure someone else here will be able to explain why.
BTW, I also created a new DIMSTYLE with a text height of 5. It probably didn't make any difference in making things appear when they should have, but it did help when it came to seeing the text in the dimensions.
Your DIMSTYLE is annotative, but the text style it uses is not.
Your active text style is not annotative, and all your text styles have a zero height (in annotative, you must provide a Paper Text height).
So all your dimensions are doing are following your hardcoded unchangeable settings, just like you set them.
Here is your file, fixed, without deleting anything. It was only following what you set it to do.
I don't believe your revised file completely fixes the problem. Everything still shows in both viewports (1:5 & 1:10) in paperspace. And the dimensions continue to show even after modifying their properties and removing unwanted annotation scales.
Dean, you may have lost sight of the OP's original problem. He was having problems getting annotative dimensions to display in two differently scaled viewports. It appears to have been solved now, but it's still not quite clear (to me at least) what was happening.
In your file I got it to work but it still required (1) removing and replacing the 1:5 and 1:10 viewports on his layout tab, and (2) going back to model space and verifying that each dimension was only associated to the annotative scale it was supposed to be associated with. In your file both dimensions were associated with 1:1, 1:5 and 1:10. That's why they showed up in both viewports. Simply fixing the associative properties wasn't enough... the viewports still needed to be redone. Once that was fixed it all worked the way it should, and the way (I think) the OP was expecting.