• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 425 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

In AC-DC circuit , Fuse affect how to passing UL test ?

Son Nguyen Ngoc
Prodigy 160 points

Dear Sir,

Below is AC-DC design for our product. In test about thunderbolt protection of EMI test, our product has failed at times 10, because fuse F1 did not operate. Thus, we would like to remove fuse F1 and add thunderbolt protection component in AC-DC design.

If AC-DC design does not have fuse, is that good ? electric safety compliance ? And more important than, if AC-DC design does not have fuse, AC-DC design could pass UL test ?

I look forward to hearing from you.

  • 0
    TI__Expert 4015 points
    Hi, I can't open your schematic, if your question relates to a specific TI part number please quote the part number in your post.

    In general application of a safety standard is due to reduce the risk of injury or damage due to electric shock, energy related hazards, fire, heat related hazards, mechanical hazards, radiation and chemical hazards. It does not specifically say that you need to use a fuse, but a fuse is typically used to limit the amount of energy that can be delivered into any fault condition to prevent the hazards mentioned above from occurring.

    It sounds like your fuse might not be correctly rated. Choosing a correctly rated UL compliant fuse should resolve your issue I would think.

    Thanks
    Billy
  • 0 in reply to Billy Long
    Prodigy 160 points

    Hi,

    Thank you for your support.

    Sorry but I don't know why attachment couldn't open. Please help me review below image. 

    With maximum current on the secondary circuit is 3 A. I also think value 2A of max current rating of Fuse on the primary circuit is so large than the value necessary.

    Besides, if I change fuse with thunderbolt protection, do you think the design is safety ? Could pass UL test ? I could not use both fuse and thunderbolt protection, because limit size of layout.

    I look forward to hearing from you.

    Best regards,

    Son.