Cooking beans in a crock pot takes around 5 to 8 hours.
I cook beans overnight in a crock pot so that they'll be ready the next day to eat and once they're cooked fully after 5 to 8 hours have passed the beans can then still be left in the crock pot and then I turn the crock pot down to the warm setting.
Then I just serve the beans when ready and I also like to throw some hamburger meat or hot dogs in the crock pot along with the beans or even ham or bacon which makes the beans taste much better.