An apparatus for providing protection from an unsafe thermal condition of an electrical connectivity, that precurse unsafe events, with a maximum temperature rating, comprising a sensor device receiving signal from a photon source indicative for said unsafe event a switch receiving signal from the sensor device indicative for said unsafe event, said switch activating an unsafe condition indicator device said sensor device is disposed within or on the electrical connectivity and is configured to detect a change of parameters of a translucent thermomorphic substance due to heat of the electrical connectivity said thermomorphic substance being selected from thermomorphic substances having one or more parameters that change at a temperature above the maximum temperature rating of the electrical connectivity, and wherein the translucent thermomorphic substance having a first end, a second end, and a transmissivity parameter, said photon source being operably coupled to the first end, the sensor device further comprising a photon monitor in communication with the second end to measure an intensity of photons to detect a parameter change of the thermomorphic substance due to heat and generate an unsafe condition signal and said switch being configured to activating said unsafe condition indicator device and to generating said unsafe condition signal characterized in that said sensor device furthermore comprising a dielectric substrate, wherein the translucent thermomorphic substance is supported on the dielectric substrate and, said sensor device further comprising a data encoder being provided on the substrate for latching said switch, said switch being provided on the substrate for receiving said unsafe condition signal. a sensor device receiving signal from a photon source indicative for said unsafe event a switch receiving signal from the sensor device indicative for said unsafe event, said switch activating an unsafe condition indicator device said sensor device is disposed within or on the electrical connectivity and is configured to detect a change of parameters of a translucent thermomorphic substance due to heat of the electrical connectivity said thermomorphic substance being selected from thermomorphic substances having one or more parameters that change at a temperature above the maximum temperature rating of the electrical connectivity, and wherein the translucent thermomorphic substance having a first end, a second end, and a transmissivity parameter, said photon source being operably coupled to the first end, the sensor device further comprising a photon monitor in communication with the second end to measure an intensity of photons to detect a parameter change of the thermomorphic substance due to heat and generate an unsafe condition signal and said switch being configured to activating said unsafe condition indicator device and to generating said unsafe condition signal characterized in that said sensor device furthermore comprising a dielectric substrate, wherein the translucent thermomorphic substance is supported on the dielectric substrate and, said sensor device further comprising a data encoder being provided on the substrate for latching said switch, said switch being provided on the substrate for receiving said unsafe condition signal.