This tutorial describes and explains how to set up Better Excerpts in a single campaign, available here.
You can create a better excerpts configuration for each campaign. Unlike the global configuration, this is a unique configuration that will be executed only in that campaign.
To configure each feature individually, you should follow the same steps as for the global configuration of the campaign. You can visit this FAQ to see it in detail:
NOTE: Keep in mind that the configurations made in each campaign will OVERWRITE THE GLOBAL CONFIGURATION OF BETTER EXCERPTS