I've seen several new users on Voat ask how the upvoat/downvoat system works. I would like to dedicate this post to explaining that system.

First, allow me to introduce you to the Voat acronyms "SCP" and "CCP". At Voat, your activity, whether submissions or comments, is measured in Contribution Points. They are split into Submission Contribution Points (SCP) and Comment Contribution Points (CCP). These figures are located right next to your username at the top right corner of any default Voat page once you log in.

Now, let's explain how the Contribution Points system works. We'll start with submissions. When you post a link (to an external site) or start a discussion (a self post), your submission automatically gets an upvoat and you get a +1 added to your SCP total. When users start upvoating/downvoating your submission, you get +1 for each upvoat and -1 for each downvoat added to your SCP total. Comments, on the other hand, start at 0 points. So you don't get anything added to your CCP total by just commenting. Your CCP total is affected only when other users start upvoating/downvoating your comments. You get +1 for each upvoat and -1 for each downvoat added to your CCP total. Note that if you upvoat your own comments, your upvoat will not be registered and nothing will be added to your CCP total.

So now that you know how the Contribution Points system works, let me explain some rules. You start your Voat journey with 0 SCP and 0 CCP. At this early stage, you have a limitation on how much you can upvoat, whether posts or comments. Your upvoats are limited by your own CCP. The rule is "Number of upvoats you have per 24 hours = Your CCP / 2". There is an exception, of course, for fresh new users who start with 0 CCP. They get 10 free upvoats per 24 hours. By positively contributing in discussions, with comments that get upvoated, your CCP starts to grow. Once your CCP total hits 20 points, which automatically gives you 10 upvoats per 24 hours, you no longer get the free upvoats. As you probably have noticed, this means that CCP is more important than SCP in Voat. So positively contributing to discussions through comments is more beneficial for you than submitting new posts.

As a new users, you also have a limitation on how much you can downvoat. Again, your downvoats are limited by your own CCP. The rule this time is different, though. It's as simple as "You can't downvoat if you don't have 100 CCP". Note that when you pass the 100 CCP milestone and aquire the downvoat ability, you can still lose it if your CCP total drops back below 100.

Voat also has some limitations for users that accumulate a negative CCP total. If your CCP total reaches -50 or less, you will be limited to 1 submission and 5 comments per 24 hours. This rule was introduced only a month ago to throttle troll account.

Update 1:
From this post by @Atko

• in order to be able to downvoat at all, user must have a higher upvoated to downvoated ratio.

Effectively, this means that a user with 100 CCP can no longer downvoat more than 100 submissions, the same applies to comments.

This piece of info might be the answer to the question "Is there a limit to downvoats?" The limit would then be your total number of CCP.

Update 2:
I've checked Voat's github source code (the Controllers folder) to verify the info and rules I provided in this post are correct. If anyone is familiar with C#, please browse through the code and let me of any comments.
I contacted @PuttItOut to verify if my interpretation of the rule mentioned in Update 1 is correct. I'm waiting for his reply.

Update 3:
In a private message from @PuttItOut, I received this quote:

We have a complete rules engine that we will be integrating into Voat soon. It's transparent and self descriptive.

Update 4:
Note that if you (or a mod/admin) delete one of your comments or submissions, the number of upvoats/downvoats of the deleted comment/submission will be deducted from your total CCP/SCP.

I hope this was helpful, but I want to make it clear that this is not an official Voat post. I'll make sure to update this, though, to always have the latest set of rules as Voat evolves.

If you notice anything missing or incorrect, please help me amend or correct it by commenting below. If you feel this can help someone, please share the link to this post so people can check and add to the discussion.