While trying to submit an edit, I received the following error message:
Too many of your edits were rejected, try again in 7 days.
And now I'm wondering, how many of my edit suggestions can be rejected per day before this happens?
I don't see the official number of edit suggestions that you can have rejected before you are temporarily banned from submitting any more posted anywhere. But I suspect that's entirely by design.
Telling people the number would make it easier for them to exploit the system by suggesting only n–1 bad edits, where n is the number of rejected edits that trips the temporary ban.
As the FAQ on suggested edits explains:
This is because suggested edits, especially on Stack Overflow, are very expensive. They require the time, energy, and effort of at least two trusted community members. If you continually submit bad edits that don't improve the site in any way, you've just wasted everyone's time. We don't appreciate that, and we'd prefer that you take some time out and watch how others edit. And then, once you get the hang of things, we're perfectly willing to give you another chance. But please don't push your luck...
Remember, you also get a reputation boost (+2) for edits that are approved, so it's in your best interest to make quality edits, as well. If in doubt about the validity of an edit, then just don't submit it. Move along and edit something else, or stop to answer a question. Let one of the other users take care of that edit.
If you'd really like to learn how to make better edits (and thus get more of them accepted), I very much recommend watching how other users (say, those with 5000+ reputation) have edited posts in the past. Any time you come across a post that's been edited, there will be a link to its revision history at the bottom, in the center. Click on it and see what changes were made. Look at what tags were used, and try to figure out why. Look at the formatting changes that were made. Look at the grammar & spelling edits. Try to imagine what edits you would have made to a post, and compare those to the ones others have made. How do they match up? Do you know why they made the changes they did? Do you see how they improve the overall quality of the post? And already, you'll be improving as an editor.
And remember that there are plenty of simple and obvious edits to suggest while you're learning and improving. Tons of people forget to format their code in their questions. Lots more people don't capitalize things properly in their question titles. Some people forget to include a tag for the programming language that they're using. Simple edits like that are almost always going to be approved.