Abstract: A monitoring device of environmental parameter values of an environment surrounding a system. The device includes a sensor to these parameters, and includes a capability to transmit, in real time, each measurement to a processing unit. The processing unit is installed in the system and includes a capability to filter the transmitted measurements. This processing unit comprises a capability to determine cycles from the measurements thus simplified as well as a capability to calculate, in real time, of a percentage of length of consumed life of the system, from the thus determined cycles.