There are three basic functions a driver can be performing, driving (operating their vehicles), on-duty (any work including driving), and off-duty (anytime free of work related responsibilities including sleeping).
A driver can be on-duty for 14 consecutive hours, of those 14 consecutive on-duty hours only 11 total hours can be spent driving. After the 14 hours has elapsed the driver must then have 10 consecutive hours of off-duty time (meant for sleeping though they are not specifically required to sleep).
A trucker cannot log more than 60 hours of driving time (not on-duty time) in the past 7 days. But, if a driver takes a 34 hour or longer consecutive off-duty break, the 7 days can be reset. A driver can also opt to limit himself to 70 hours in the past 8 days. Again a 34 hour consecutive off-duty period will trigger a reset.
This is the gist of it. There are a number of other rules which provide provisions for things like bad driving conditions, secondary jobs, breaking up the on-duty hours, etcetera, but this will give you an idea of how much a driver can legally do in one day. Drivers keep a log of all of their activities and any issue with this log can result in relief of trucker duty. The government takes these rules very seriously.
Need update for ELD.
I’ve been driving a truck for over 20 years and this new ELD update is one of the worst things to ever happen to the industry. Write that down!