By definition, the ESL – Engine Speed Logger is designed to monitor RPMs of race cars but not only. ESL is able to capture the exact moment when and where the over rev happened.
This technology also allows to define at which value the limiter is set to (It only applies to ignition control rev limiters). This information is essential for diagnostics use but also for engine monitoring.
On top of its main purpose it can also record:
As example of use of this system, EM Motorsport is providing the ESL – Engine Speed Logger for one very specific purpose and that is to accurately monitor and log the RPM of the engine of the cars that participate in the FIA Masters Historic Sports Cars championship.
The engine speed logger uses two main connections to acquire an accurate reading of the engine speed.
The first and mandatory connection is to the ignition coil.
The second and optional connection is to the protected output that some of the newer ignition systems like MSD or CDI provide.