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  1. #1
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    What's an "isolation diode"?

    Hi friends.

    I came across a interesting power point presentation https://uspas.fnal.gov/materials/11S...Topologies.pdf

    As it's usual with ppp's they don't give detailed info, so I'm wondering how that isolation diode (on the right connected to the -300V) is working and what it's isolating against and how it is connected to the circuit?

    Click image for larger version. 

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  2. #2
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    Re: What's an "isolation diode"?

    usually means to prevent back feed - the whole ckt looks dicey to me - not well thought out ...



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    Re: What's an "isolation diode"?

    Quote Originally Posted by Easy peasy View Post
    usually means to prevent back feed
    I thought it might be some sort of isolation to prevent parasitic capacitance since it stood there all alone.

    Quote Originally Posted by Easy peasy View Post
    the whole ckt looks dicey to me - not well thought out ...
    Nevertheless they got the money and built it see pictures page 16-17, and they are also using something called "Equipotential Ring" - what's that?



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    Re: What's an "isolation diode"?

    Methinks that ckt has been "modified" for publication

    - - - Updated - - -

    equipotential ring is exactly what it says, an actual ring, or ring of devices at the same potential ( to ground often, or to neg or some other fixed ref point )

    - - - Updated - - -

    https://www.google.com/url?sa=t&rct=...TlF-xJKIir01V_



  5. #5
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    Re: What's an "isolation diode"?

    Quote Originally Posted by Easy peasy View Post

    equipotential ring is exactly what it says, an actual ring, or ring of devices at the same potential ( to ground often, or to neg or some other fixed ref point )
    That's exactly how I would have answered that question if someone posed that to me Besides the obvious which is shown in the pictures of the thing, allow me to rephrase my question; how does a equipotential ring work? It must be there for a purpose, and what is that?

    Thanks for the link, I can see the iso diodes now in Fig. 1. Have you noticed the resemblance with BradTheRads suggestion here https://www.edaboard.com/showthread....=1#post1656904 almost same thing but with less diodes.



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