Standardisation of the static resistances of fluorescent lamp cathodes and new data for preheating

During the past few years the electrical data of the cathodes of some fluorescent lamps were standardized. An explanation is given of the choices made for standardizing the static resistances of the cathode coils. Also in the forthcoming new editions of the IEC standards for fluorescent lamps (IEC 60901 "Single-capped fluorescent lamps" and IEC 60081 "Double-capped fluorescent lamps") several lamps will get a new and more general description for the preheating of electrodes. The physical background and justification for this description are given.