When is a draft complete?

I am working away on draft two of novel number two and I am not sure, but I think it might be time to set it aside.

I've done some major changes, deletions, rewrites and rearranging.

What I'm not sure about, is when you know it's time to say "enough" to one draft and set it aside until the next draft.

Help! How do you, dear reader, know when your draft is complete?