There's no such thing. Traccar doesn't have a default connection timeout.
Read this please Leonardo: https://www.traccar.org/forums/topic/offline-status-from-traccar-client-always-takes-10-min-to-display-it-on-the-web-client/#post-83648
In a reply a user talks about the traccar configuration, hope it helps
traccar comes by default that if it does not receive data from the device within 7 minutes it goes offline, you can change this for metro