IMPORTANT - This article refers to the Web Dashboard Module for the Desktop version of Snapshot - NOT Snapshot.Live, the Cloud Dashboarding tool.
The Snapshot Web Dashboards module does not automatically refresh, like the option in the Desktop version where you can set the refresh rate down to minutes.
The data is loaded directly from the database when the page loads (i.e. there is no cache).
The user would manually refresh when needed. The other option is to add a Browser extension (add on) and set that extension to Auto Refresh.