Hello everybody (from Malaga)! Thank you for your comments, particularly to Rich Nute for his clear exposition.
I have seen the argumentation about IEC 601. I did not include IEC 601 because it is the standard in which, perhaps, I better understand the differences. But, of course, you can write IEC 601 like IEC 950 + complements, though the complementary standard should be rather large. However, I could include many other standard I didn't for simplification reasons. For example, the standards considered of electrical appliances (not electronic) like IEC 335. Long time ago, electrical and electronic appliance was absolutely separated. That is not true at this moment. Electronic is included in almost all the appliances and you can find motors and other electrical components in many electronic appliances. One example of the mixture is the electronic insects killer (IEC 335-2-59), included in the scope of IEC 335 although it is an electronic appliance. However, normalization committees are absolutely separated. The result is different tests to check the same requirements (putting out particular requirements). We could speak about many other standards like IEC 924, IEC 928, IEC 730, IEC 215, IEC 1046, etc. But my main problem is to find justification to the differences. Let me go back to flammability requirements. Rich is right, abnormal conditions are checked in each standard then, you can get some warranties about the fire risk. However, description of how to test abnormal conditions are much more extensive in IEC 950 than in other standards. So, some one can infer that flammability requirements in IEC 950 could be weaker. But it is the opposite. For one equipment on the border between IEC 950 and IEC 65, supposed it pass all abnormal tests, if IEC 950 is applied, the manufacturer has to used good and expensive plastic materials (minimum HB class, V1 for fire enclosure). But if IEC 65 is applied, the manufacturer can save a good money in plastic quality. In my position like a testing laboratory, it is difficult to explain to my clients so big difference. In the future, I will put in your consideration some other important differences between standards with difficult justification. I hope that normalization committees read and answer. Thank for your comments. ======================================================== Juan P. Pena / Electrical Safety Area Company: CETECOM, S.A. (http://www.pta.es/ing/empresas/cetecom.html) e-mail: [email protected] The opinions expressed are personal, not necessarily of my company. ========================================================
