Compliance of IEC61010-1 and VDE0884-10

Hello,

 

I am confused about the safety ratings of the part ADuM4120. Its datasheet states reinforced insulation for a working voltage of 400Vrms to meet IEC61010-1, while the rating for reinforced insulation with VDE0884-10 is 849Vpeak.

 

According to the section 14 of IEC61010-1, this norm accepts any part meeting another recognized safety standard. This means that ADuM4120 would meet reinforced insulation for 849Vpeak because it complies with VDE0884-10. So, why the rating specified for IEC61010-1 in the datasheet is lower (400Vrms)?

 

Thank you in advance.

  • Hello Mark,

     

    In this design the isolator separates a low-voltage stage from a floating section that can be externally driven with voltages up to 500Vrms / 5MHz. Even if the isolated driver is not switching, its barrier can be subjected to these levels because of this external signal driving the isolated sector.

     

    Due to the complexity to estimate the isolators lifetime, I think that it may be better to assume that they can break and include additional protection against isolation failures (that in turn warns about these events in some way).

     

    Best regards,

    Victor M.