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Eskimo007's avatar
Eskimo007
Explorer
Aug 14, 2021

"Groovy" flat fuses VS non-groovy

I recently needed to replace a 40amp DC flat fuse between my RV battery and inverter, and had the hardest time trying to insert the spare fuse that the original owner had provided. Upon (very) close inspection, I noticed that the replacement fuse although the exact same size and appearance as the burnt out one had some grooves on each side, whereas my replacement did not. Needless to say, trying to force the replacement in the holder brought no joy.


Does anyone know what the difference is between the 2 types? I'm thinking maybe slo-blow or not? Looking at the transparent casing of the fuses, I can see the inside is different.

19 Replies

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  • Fisherman's avatar
    Fisherman
    Explorer
    Aug 15, 2021
    I'm going with what DrewE said, most likely makes for a tight positive contact.
  • DrewE's avatar
    DrewE
    Explorer II
    Aug 15, 2021
    I don't think the grooves signify anything, nor ought they interfere with the fuse insertion. I think they're just an artefact of the way the prongs are manufactured on the one fuse (they appear to be laminated out of a couple thicknesses of metal on the one, vs. cut from a single thicker piece on the other). I might be wrong, of course, but it seems quite unlikely to me that they are significant.

    Perhaps you simply weren't applying enough force to get the fuse into the socket? Sometimes these sorts of things can be really tight and need more persuasion than one would generally expect.
  • NRALIFR's avatar
    NRALIFR
    Explorer
    Aug 15, 2021
    I don’t think I’ve ever noted that difference before, but I see what you mean now. If the device the fuse is for uses those grooves as a “key”, you can only use that style of fuse.

    Most of the maxi fuses you can order on Amazon (that have decent pictures) appear to have the grooves, but that doesn’t necessarily mean that’s what you’re going to get.

    I guess I would just take your old fuse to an auto parts store and buy one that looks the same.

    :):)
  • NRALIFR's avatar
    NRALIFR
    Explorer
    Aug 15, 2021
    Jacques, use this link to post a picture on this forum.

    IMGUR Photoposting Link

    Drag and drop your image, or use the SELECT button to navigate to the image on your device, and it will upload to the IMGUR host site. It will then give you a link that you copy and paste into the forum Quick Reply box.

    :):)
  • Eskimo007's avatar
    Eskimo007
    Explorer
    Aug 15, 2021
    It's a 40A like the Maxi. Will try to add a picture to my post that clearly shows the grooves above the blades on both sides.




    (cant figure out how to post pictures, says link removed)
    1drv.ms/u/s!AlUCXH-477GAipJtv8NIRuvampPKpg?e=bT3pNF


    1drv.ms/u/s!AlUCXH-477GAipJuc1QtvC3nggC3QQ?e=AfB3RO
  • NRALIFR's avatar
    NRALIFR
    Explorer
    Aug 14, 2021
    Sounds like you’re talking about a blade type fuse, but you might want to clarify that before we get off too far in the weeds.

    Is it one of these?



    :):)
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Aug 14, 2021
    I think the only difference is the maker.. "Grooves" make it easier to grip with fingers.
    I use tools to insert fuses. generally works

    Compare the Tabs that come out of the fuse. I've seen some that I think are bigger.
  • Dusty_R's avatar
    Dusty_R
    Explorer
    Aug 14, 2021
    Did you try turning the fuse around? But I don't know why a fuse would be directional.

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