Announcement

Collapse
No announcement yet.

Luna X-1 Enduro FS ebike MANUAL

Collapse
This is a sticky topic.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Hi Pax, just wondering, but is there a 12V DC charger for the Luna 48V battery? If so, do you guys offer it? I'm looking to charge the battery directly from a DC source -- like a 12V car battery.

    Comment


    • AZguy
      AZguy commented
      Editing a comment
      FWIW I could not get more than ~1.6A out with 13.5V in on the MPT7210... if you can live with that charge rate it works pretty well

      We wrote it up here: https://electricbike.com/forum/forum...-packs-from-12

      No matter what you use you'll need a 12V source that can put out a fair bit of power - at that low charge rate it still took something like 6.5-7A... it's likely only practical when the engine is running (or a generator) and then it would still be a very long drive to fully charge an empty battery

      I think a better approach is just brute force it by wiring in a decent 400+W inverter directly to the battery (with a fuse of course) and then just run a conventional 120V (or 240V?) 2-2.5A charger off of that... this is what I've done and it's done a good job of putting some charge in the battery... I've also done a 2A charger with an inexpensive 300W inverter and that worked, but dang that inverter got hot...

      Spare batteries really, really help most of the time =]

    • paxtana
      paxtana commented
      Editing a comment
      Oh bummer.

      Man it's too bad we can't find a variable lab power supply that can take 12vdc input and output up to 60vdc. Kind of a surprise something like that does not exist. While it would be a relatively limited use case I assume it would be cheaper to produce than a typical power supply since it would not be changing from ac to dc, and even a fancy boost converter is still just a boost converter.
      Last edited by paxtana; 1 week ago.

    • AZguy
      AZguy commented
      Editing a comment
      It's straightforward - especially if we're not worried about having a common negative (battery under charge and power source negative connected together) which should not be a concern here - isolation would make it a bit more complicated but not really all that bad

      Sometimes I wonder if its use is as practical as it sounds at first blush. Even a 2A charge rate will draw enough current that we'll need a power source capable of around 10A or more so if a vehicle we're talking about engine running or perhaps a deep cycle battery. If we're talking engine running we likely want fast charge too, maybe 3-5A, so we get a charge in a couple of hours or so tops and then it snowballs requiring 20A or more, give or take and so should be hardwired at that point... and that's for a bicycle battery... if a light moto (a la sur-ron) then it really gets out-of-hand

      FWIW, should be able to parallel a couple of those MPT-7210's to get 3A'ish but I only have one so can't say for sure how that would go - should work though
Working...
X