IEC 60505 pdf download.Evaluation and qualification of electrical insulation systems
1 Scope
This International Standard establishes the basis for estimating the ageing of electrical insulation systems (EIS) under conditions of either electrical, thermal, mechanical, environmental stresses or combinations of these (multifactor stresses). It specifies the principles and procedures that shall be followed, during the development of EIS functional test and evaluation procedures, to establish the estimated service life for a specific EIS. This standard should be used by all IEC technical committees responsible for equipment having an EIS.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.3.1 General terms 3.1.1 electrical insulation system EIS insulating structure containing one or more electrical insulating materials (EIM) together with associated conducting parts employed in an electrotechnical device 3.1.2 electrical insulating material EIM material with negligibly low electric conductivity, used to separate conducting parts at different electrical potentials [IEC 60050-21 2:201 0, 21 2-1 1 -01 , modified] 3.1.3 reference EIS established EIS evaluated on the basis of either a known service experience record or a known comparative functional evaluation 3.1.4 candidate EIS EIS under evaluation to determine its service capability (with regard to electrical, thermal, mechanical, environmental or multifactor stresses) 3.1.5 intended life design life of an EIS under service conditions 3.1.6 estimated life expected service life derived from either service experience or the results of tests performed in accordance with appropriate evaluation procedures, or both, as established by the responsible organization or technical committee 3.1.7 evaluation establishment of relationships between service requirements and life data obtained from service experience analysis or from the results of functional tests 3.2 Terms related to service stresses and ageing 3.2.1 ageing stress electrical, thermal, mechanical or environmental stress whose action on an EIS causes irreversible property changes 3.2.2 potentially destructive stress stress in service which can cause the failure of the aged EIS, alone or in combination with other stresses 3.2.3 service conditions combination of stresses and duty that are to be expected in a specific application of an electrical device 3.2.4 reference operating conditions service conditions of the equipment to which the test conditions of the functional test procedure are related 3.2.5 service requirements specified stresses, intended performance and duty of an electrical device 3.2.6 service experience the quantitative and/or qualitative record during service, with or without failure of an EIS 3.2.7 ageing irreversible changes of the properties of an EIS due to action by one or more stresses NOTE 1 Some changes (e.g. hydrolytic changes) can be partly reversible if the ambient conditions change. NOTE 2 Ageing leads to degradation of the EIS. 3.2.8 intrinsic ageing irreversible changes of fundamental properties of an EIS caused by the action of ageing factors on the EIS 3.2.9 extrinsic ageing irreversible changes of properties of an EIS caused by action of ageing factors on unintentionally introduced imperfections in the EIS 3.2.1 0 interaction modifications of the type or degree of ageing produced by the combination of two or more stresses relative to their ageing effect if acting individually on separate objects 3.2.1 1 direct interaction interaction between simultaneously applied stresses that differs from that occurring with sequentially applied stresses 3.2.1 2 indirect interaction interaction which occurs between simultaneously applied stresses, which remains unchanged when the factors are applied sequentially 3.3 Terms related to testing 3.3.1 functional test procedure to obtain information about the suitability of an EIS under specified conditions 3.3.2 test object sample of original equipment or part thereof, or model representing the equipment completely or partially, including the EIS, to be used in a functional test3.3.3 accelerated ageing ageing resulting of an increase in the level and/or frequency of application of the stress beyond normal service conditions 3.3.4 accelerated test functional test applying accelerated ageing to shorten testing time 3.3.5 conditioning subjecting a specimen to an atmosphere of a specified relative humidity or complete immersion in water or other liquid, at a specified temperature for a specified period of time 3.3.6 prediagnostic conditioning variable or fixed stresses, which can be applied continuously or periodically to an EIS to enhance the ability of a functional test to detect the degree of ageing NOTE Prediagnostic conditioning may cause additional ageing.
IEC 60505 pdf download
