The May issue of “Eletricidade Moderna" is online. The article “Fire Safety Lights - Comparative Analysis - Part 1”, on page 22, focuses on the differences between autonomous batteries and central batteries and their technical and economic characteristics, in the light of a European experience. This study, to be published in two issues, also suggests a comparison of relative costs for application in Brazil. See on page 34 the article “Parametric analysis of energy-efficient motors”, which presents a study on how manufacturers are working to meet the efficiency standards of three-phase squirrel-cage induction motors: reducing stator and rotor resistance and / or increasing circuit resistance magnetization. Furthermore, on page 48, the article “Effect of voltage fluctuations LEDs and compact fluorescents”, where, through theoretical and laboratory studies, the effect of voltage fluctuations on the operation of LED and compact fluorescent lamps has been evaluated, which have been gradually replacing the incandescent lamps. This issue brings also the news “Conduits” and “LV Switchgear & controlgear” buyers’ guide.