DANSK DSF/PREN IEC 61857-33 PDF

This part of IEC 61857 series is applicable to multifactor evaluation of an EIS for applications where the stresses of the application are a combination of the factors identified in IEC 60505. The severe operating conditions are expected to occur during operation at elevated temperatures. This part establishes the procedure to evaluate the influence of stresses on the performance established following the thermal classification of the EIS. The thermal classification is established in Step 1 where the only ageing factor is thermal. The candidate EIS is first evaluated based on thermal stress only. This evaluation is defined as the baseline of the candidate EIS. Evaluation of the additional factors applied at the elevated temperatures provides the measurement needed to establish the influence of the additional factors on the performance of the baseline EIS. IEC 60505 provides four categories of stresses or ageing factors which influence the performance of products in use under a wide range of operating conditions. In 60505 the factors are presented as Thermal [T], Electrical [E], Environmental [E] and Mechanical [M]. In this part of 61857, Environmental [E] is replaced with Ambient/Environmental [A] to remove possible confusion of having two factors represented by the same letter E. For this part of 61857 the factors are presented with Thermal by T, Electrical by E, Ambient/Environmental by A and Mechanical by M.