DIN EN 50443:2012-08

This standard specifies limits for the interference effects produced by high voltage a.c. railway and power supply systems on metallic pipelines. This standard applies to all metallic pipelines irrespective of the conveyed fluid, for example, liquid or gas, liable to be interfered by high voltage a.c. railway and high voltage a.c. power supply systems. The limits for the interference quantities are designed in a way that they can be tolerated on the metallic pipeline, by the equipment connected to it and by persons working on them or in contact with them. A.c. power supply systems or a.c. electric traction systems may cause voltages to build up in pipeline systems, running in the close vicinity, due to one or more of the following mechanisms: - inductive coupling, - conductive coupling, - capacitive coupling. This standard deals with the situations where these effects may arise and with the maximum tolerable limits of the interference effects, taking into account the behaviour of the a.c power systems both in normal operating condition and/or during faults. It relates to phenomena at the fundamental power frequency (for example, 50 Hz or 16,7 Hz). For determination of the reliability of interferences caused by an a.c. power system with respect to a metallic pipeline system, the following steps shall be followed according to this standard: a) specification of the interference distance to be observed; b) specification of the interference situations to be observed (worst case); c) selection of the occurring coupling types to be considered; d) selection of the occurring interference effect(s) to be considered; e) evaluation of the result(s) of the interference for each interference effect selected in the previous step; f) selection of the permissible limit for each result evaluated in the previous step; g) selection of the most stringent limit if more than one interference is to be considered; h) evaluation of the interference results of metallic pipelines by calculation or dimensioning; i) comparison of the interference results with appropriate limits: if the comparison shows that the interference situation is inappropriate, mitigation measures shall be taken to make the interference situation acceptable. The aforementioned steps are described in this standard. Suggestions concerning the interference situations to be examined are given in Annex A. Suggestions concerning the appropriate calculation methods are given in Annex B, suggestions concerning the appropriate measurement methods are given in Annex C, suggestions about the use of mitigation measures are given in Annex D and suggestions for management of interference are given in Annex E. This standard does not apply to all aspects of corrosion, the coupling from a.c. railway and power supply systems with nominal voltages less than or equal to 1 kV, interference effects on the equipment not electrically connected to the pipeline. The responsible committee is Subcommittee UK 767.6 "Schutz von Einrichtungen der Informationstechnik gegen Überspannungen und niederfrequente Felder" ("Protection of information technology installations against overvoltage and low frequency fields") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE. UK 351.2 "Ortsfeste Anlagen" ("Fixed installations") has been involved in the national treatment of this standard.