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Ripple on low voltage

Peterd
I look after a small fairground type railway. It is powered via a transformer and full wave rectifier and runs at around 35 volts. At recent inspections it has been noted that it fails as there is around 24 volt ripple on the 35 volt dc, which is not surprising as there is no smoothing. Apparently according to the person undertaking the inspection, who states it is to bs7671, the ripple should be no more than 10% ripple, however I cannot find any such requirement.

Has anyone got any experience of this type of thing, I am loathe to add a capacitor to smooth the dc - it would have to be probably around 0.1F, and ripple current in it could well be a problem.

Any thoughts on this would be appreciated, is there an actual requirement on ripple, or is it OK to just have full wave rectified dc as long as the peak voltage does not exceed the elv limits of 120v dc or 50 v ac rms .
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    Elizabeth Morgan:
     


    mapj1‍ To delete the files, you should be able to see a dustbin next to the file name under the 'attached files' heading in your published post.




    Thanks for that. I can see no dustbins ? Any tricks I need to do  to make it appear ?

    What I see is this  (Firefox, Linux mint 17in monitor... it should not matter. perhaps it does.)

    Later EDIT

    AHA changing the attachements to a post is not "editing" it at all. You do not start the editor.

    I must say that is not obvious, and I would not have guessed it. Mind you 3 dots for 'edit' is not the most obvious either.

    cheers

    Mike.

     


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  • 0
    Elizabeth Morgan:
     


    mapj1‍ To delete the files, you should be able to see a dustbin next to the file name under the 'attached files' heading in your published post.




    Thanks for that. I can see no dustbins ? Any tricks I need to do  to make it appear ?

    What I see is this  (Firefox, Linux mint 17in monitor... it should not matter. perhaps it does.)

    Later EDIT

    AHA changing the attachements to a post is not "editing" it at all. You do not start the editor.

    I must say that is not obvious, and I would not have guessed it. Mind you 3 dots for 'edit' is not the most obvious either.

    cheers

    Mike.

     


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