I don't think the format is configurable.
In case it helps someone: I modified the Traccar web code in src/utils/formatter.js
and added the following line in formatNumericHours
:
const seconds = Math.floor((value % 60000) / 1000);
return `${hours} ${t('sharedHourAbbreviation')} ${minutes} ${t('sharedMinuteAbbreviation')} ${seconds} ${t('sharedSecondAbbreviation')}`;
traccar 6.5
"Is it possible to display the duration of a stop in seconds in the stop report?"
thanks