EN 41003 : régles particulières de sécurité pour les matériels destinés à être reliés aux réseaux de télécommunications / Comité Européen de Normalisation Electrotechnique
EN 50008 : low voltage switchgear and controlgear for industrial use. Inductive proximity switches. Form A, for direct current, 3 or 4 terminals / European Commitee for electrothecnical Standardization
Signalling on low-voltage electrical installations in the frequency range 3khz to 148,5 khz : part 1: general requirements, frequency bands and electromagnetic disturbances: EN 50065 -1: 1991 / European Commitee for Electrothecnical Standardization
EN 50065 -1/A1 : 1992: signalling on low-voltage electrical installations in the frequency range 3khz to 148,5 khz: part 1: general requirements, frequency bands and electromagnetic disturbances: amendment A1 / European Commitee for Electrothecnical Standardization