Lug spacings

Discussion in 'Electrical Systems' started by fallguy, Apr 12, 2021.

  1. fallguy
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    fallguy Senior Member

    Anyone know if this zero clearance lug spacing is allowed for a series connection? I have no room for sheathing.

    FB08F772-D697-4CCB-8793-A04B6BA5747B.jpeg

    Also, how evil is it to use 3/8" holes on 5/16" lugs?

    thanks
     
  2. fallguy
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    fallguy Senior Member

    I made a loop

    A98B746F-C557-4808-9006-C0046EBCBE5C.jpeg
     
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  3. kapnD
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    kapnD Senior Member

    You could turn one or both the batteries 180* and pick up some room between the lugs.
     
  4. kapnD
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    kapnD Senior Member

    I would not recommend the close coupled option.
     
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  5. fallguy
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    fallguy Senior Member

    Thanks KapnD.

    I am plugging along. 61D5E99A-F35F-4A9A-90C8-35C87C9437FE.jpeg
     
  6. jehardiman
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    jehardiman Senior Member

    It it done on commercial/military battery...but it is a solid copper bar with a milled minimum groove so they can be severed if needed. Much bigger batteries than those.
     
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  7. Rumars
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    Rumars Senior Member

    The loop is the right way. You can't fix those batteries in place rigidly enough to use a non flexible coupler, and even if you could you would have to use an omega shaped bar to account for thermal expansion. The larger hole is not a big problem, you loose some contact area but that's only important if you draw big amps. Put a wide washer of the right size under the nut to spread the load, and I like to use locknuts for this.
     
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  8. fallguy
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    fallguy Senior Member

    I don't like locknuts for most any stainless. But I appreciate the comment because I best add lockwashers and have not done so in the past if I ran rings onto the lugs for simpler systems for fear of wrecking the rings. Here, not the case. All this gets is a fuse terminal to the T holder.

    Also, thanks on the lug size question. I have a lot of gear, but the mrbf fuse holder (not pictures) is 3/8" onto a 5/16" lug

    Thank you all for posting.

    Part of the reason I didn't want to loop is the 2/0 wire was outside in 40 degrees and was not wanting to bend down to 3" witbout getting pretty long.

    okay...another question

    For the series connection (the loop), is there an appropriate color? Is it supposed to be red or yellow? My pea brain says red, but I saw a few black versions online which would be yellow here.

    again, thanks

    My battery case will be getting redone and painted after the wiring is done....fyi...I spent a day or two trying to locate the digital switches on reverse and finally gave up after it became just too difficult an arrangement
     
  9. Rumars
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    Rumars Senior Member

    I would not use lockwashers, you need a flat washer over the lug and that makes all lock washers useless. But you can double nut, that's also secure.
    For all I know there is no standard for the series connection colour, red is just fine.
     
  10. fallguy
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    fallguy Senior Member

    Isn't the purpose of the lock washer to keep upwards pressure on the nut? I don't see how that is not effective.
     
  11. fallguy
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    fallguy Senior Member

    96B0F9B2-508D-4295-9BC7-9602F655F596.jpeg BDC672EB-4AA3-4831-9AA7-A3AC9A7F8A85.jpeg Work continues..

    It sure is a pita getting 2/0 into the lugs once stripped.

    I'm gonna build it and probably take it apart and repair the xtra holes, btw.
     

  12. rangebowdrie
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    rangebowdrie Junior Member

    AFAIK their is no official designator, however, on one one job where I installed 12 8volt batteries to make 3 banks of 32volts, I used red and yellow on opposite ends of the inter-connecting cables.
    The routing between batteries wanted the cables and the batteries to lay in a certain path/position.
     
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