I need to feed some digital inputs to the AVR from a external source.
This equipment will be used as a vehicle datalogger where the inputs will be isolated via a optocoupler (PC817)
The inputs of the optocoupler will be connected to the vehicle horn, lights etc.
The logger will log the events and also count the total duration of each inputs.
Is there any way to protect the optocouplers? I am fearing a load dump from the inductive and resistive loads might damage the optocouplers.
The vehicle is a 24V system.