An ELD (Electronic Logging Device) is a device that is used in commercial trucks to track hours of service (HOS). ELD technology automatically records a driver’s driving time and other aspects of their HOS records to allow for easier, more accurate HOS recordkeeping.

An ELD device monitors a vehicle’s engine to capture data on:

• Whether the engine is running,
• Whether the vehicle is moving,
• Miles driven, and
• Duration of engine operation in hours

The reason for measuring and recording driver hours behind the wheel is public safety—specifically, as it relates to drivers falling asleep at the wheel. It also stops the truckers from driving that last hour home when they’ve already driven 8 straight hours (typically the largest number of at-fault accidents occur from this last hour. Drivers may not want to stop as they’re paid by the mile, not by the hour or on fixed salary).

In the past, truck drivers logged everything via a spiral book. These log books were always fudged and not truly enforceable from a law enforcement standpoint. The ELD and HOS are basically “data loggers” that record all driving and hours of “behind the wheel” use of trucks. The data logger type data port is accessible by Law Enforcement at Truck Stops, random highway stops, etc.