Permissions management: manage Exporter permissions within Jira's global settings (System → Global permissions → Access to Exporter app).
Default Access: By default, Exporter will enter all groups that have access to Jira applications such as Jira Software, Jira Business Manager, and others.
Restricted Access: Access to the application will be limited to the user groups specified in the global permissions.
** Note that any logged in user can be added as a recipient of a scheduled export and will be able to download files.
Just go to Jira Administration → Manage Apps → Exporter → Administration
In the first section you will find the text box to set the issue limit.