DIN EN 60076-1:2012-03

The current German version of Part 1 of IEC 60076 is a complete revision of the previous edition. It applies for power transformers with two or more windings which, by electromagnetic induction, transform a system of alternating voltage and current into another system for the purpose of transmitting electrical power. It applies to three-phase and single-phase power transformers (including auto-transformers) with the exception of certain categories of small and special transformers such as: - single-phase transformers with rated power less than 1 kVA and three-phase transformers less than 5 kVA; - transformers, which have no windings with rated voltage higher than 1 000 V; - instrument transformers; - traction transformers mounted on rolling stock; - starting transformers; - testing transformers; - welding transformers; - explosion-proof and mining transformers; - transformers for deep water (submerged) applications. When IEC standards do not exist for such categories of transformers (in particular transformers having no winding exceeding 1 000 V for industrial applications), this part of IEC 60076 may still be applicable either as a whole or in part. The new edition of this standard has been extended in the scope from oil-immersed to liquid-immersed transformers. Now the permitted harmonic distortion for currents and voltages during service of a power transformer as well as the permitted mechanical accelerations during transport and earthquakes are quantitatively specified. Requirements for vacuum, pressure and leak tests on tanks have been specified and informative annexes for condition monitoring systems and for environmental and safety aspects have been added. For unusual service conditions, special designs of the transformer are required. These conditions include a high installation altitude, extremely high or low coolant temperatures, tropical humidity, earthquake activity, significant pollution, unusual harmonics of the voltage or load current, high solar radiation and intermittent load. One clause of the standard deals with DC currents and refers to a possible DC magnetization of the core. The extent of routine, type and special tests has been extended; in particular mechanical tests on the tank have been described. A functional method for specification has been described, requirements for liquid preservation systems have been added and in Annex A an informative checklist is supplemented. This standard does not contain requirements for the mounting of transformers in positions accessible to the general public. For those categories of power transformers and reactors which have their own IEC standards, this part is applicable only to the extent in which it is specifically called up by cross-reference in the other standard. Such references exist in the standards for the following categories: - reactors in general (IEC 60076-6); - dry-type transformers (IEC 60076-11); - self-protected transformers (IEC 60076-13); - gas-filled power transformers (IEC 60076-15); - transformers for wind turbine applications (IEC 60076-16); - traction transformers and traction reactors (IEC 60310); - converter transformers for industrial applications (IEC 61378-1); - converter transformers for HVDC applications (IEC 61378-2). The responsible committee is K 321 "Transformatoren" ("Transformers") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.