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McKenziek's avatar
McKenziek
Explorer
Oct 07, 2013

Blowing 125 Amp Fuse after converter upgrade

I've completed the build of my converter upgrade using RoyB's schmeatic (below) and I have an issue that I think I have the answer to but want to run it by the forum.

I've blown the 125amp ANL fuse twice now, both times on battery power while raising the auto-levelers which I assume must use a lot of juice. The fuse protects the wire between the converter and the 12 volt distribution center.

I believe the 20' run from the batteries to the 12 volt distribution panel using the stock 6ga wire is too long for the wire size. The converter can accept up to 2ga.

Just want to see if replacing the run with 2ga or even 4 ga will fix my problem before I drop the coin.
RoyB wrote:
I upgraded my real old single mode converter/charger to a WFCO 45AMP smart mode converter/charger only to find out I could never get my WFCO unit to go into smart mode charging.

Then I purchased a PD9260C 60AMP smart mode converter/charger but I mounted it stand alone closer to the battery bank. I decided to leave the WF8945 unit in its location in the bottom compartment of the WF series Power Distribution Panel.

I ran a 120VAC connection to the PD9260C from another circuit breaker in my panel.

I most of the time use the PD9260C by just flipping the circuit breaker for this unit and have the WF8945 converter turned off by flipping its circuit breaker.

I only have the brand new WF8945 converter around for back-up purpose. I only have one converter turned ON at a time however I don't think it would harm anything having both of them on. It just didn't seem like having two converter units ON at the same would be a good idea.

You can see where my two converters are installed in this floor plan drawing of my trailer...


This is a schematic diagram of my how my two converters are wired in my setup...


There is some posts on here where a B&D VEC1093DBD smart mode portable battery charger was being used along with the on-board trailer converter/charger to get to full 100% charge state on the batteries quicker.

Roy Ken
  • RJsfishin's avatar
    RJsfishin
    Explorer
    Oct 07, 2013
    What does a fuse in the output of the converter have to do w/ the levelers ?
    The 60 amp output of the converter will not blow a 125 amp fuse. And seems the 6ga wire would smoke before blowing a 125 a fuse. And a 20 ft converter run to the batteries thru #6 wire ?? There ain't nothing/something right about this whole thing.
    Now if the converter is shorting out, then it could blow the 125a fuse,.....if the wire didn't smoke first.
  • tenbear's avatar
    tenbear
    Explorer
    Oct 07, 2013
    What levelers are you using? That might provide a clue to the problem.
  • tenbear's avatar
    tenbear
    Explorer
    Oct 07, 2013
    I would follow the leveler wiring and look for maybe a pinched wire that might have been caused when you replaced the converter.

    Of course, it could be an unrelated problem but that is unlikely.
  • tenbear's avatar
    tenbear
    Explorer
    Oct 07, 2013
    McKenziek wrote:
    tenbear wrote:
    Did your levelers work with the #6 wire before you changed the converter? If they did, the #6 wire is not the problem. Look for a wireing problem.

    OTOH, if you replaced a Magnetek/Parallax converter with a PD9260 or similar converter, you might want to replace the #6 wire to reduce the voltage drop when charging the battery


    The levelers worked fine and what you stated makes sense. I will double check my wiring but why would everything work fine until I level?

    The wiring problem (short???), assuming that is what it is, only becomes a part of the circuit when the power is applied to the levelers.
  • RVUSA's avatar
    RVUSA
    Explorer
    Oct 07, 2013
    just a guess, but if all 4 levelers try and run at the same time and they take 50 amps each, 50 * 4 > 125. You can test for that by only hooking up 1 leveler at a time and see if it still blows the fuse. Plus if one is wired wrong it will help in determining isolating which one.

    I would be tempted to wire and fuse each leveler separately.
  • McKenziek's avatar
    McKenziek
    Explorer
    Oct 07, 2013
    smkettner wrote:
    Did the levelers work before or were they just added?
    If added what were the power/wiring requirements?


    They worked fine. I will check tomorrow if they're running from the fuse panel or directly from the batteries.
  • time2roll's avatar
    time2roll
    Nomad
    Oct 07, 2013
    Did the levelers work before or were they just added?
    If added what were the power/wiring requirements?
  • McKenziek's avatar
    McKenziek
    Explorer
    Oct 07, 2013
    smkettner wrote:
    125 amp fuse opens? I think you have a short.
    I can't imagine the leveler would draw more than 50 amps.

    WFCO might be rated #2 but if you use fine strand tinned wire it will be near impossible to insert every strand. I recommend #4 max.


    It it was a short I would think the fuse would blow immediaty once I turn on the levelers. In this case the auto leveling runs for about 20 seconds before the fuse blows.
  • McKenziek's avatar
    McKenziek
    Explorer
    Oct 07, 2013
    tenbear wrote:
    Did your levelers work with the #6 wire before you changed the converter? If they did, the #6 wire is not the problem. Look for a wireing problem.

    OTOH, if you replaced a Magnetek/Parallax converter with a PD9260 or similar converter, you might want to replace the #6 wire to reduce the voltage drop when charging the battery


    The levelers worked fine and what you stated makes sense. I will double check my wiring but why would everything work fine until I level?

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