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  1. #1
    RC Racer
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    Lipo at end of run is at 3.75-3.8V per cell.

    I'm running the Traxxas 7600 mah 2s Lipo in my Summit with the LVD ESC and I'm consistently ending when it obviously is out of power and the high range gear is slow and lazy. I would think that I'm near the low voltage cut out, but when I connect to the Onyx 245, I'm always at or slightly above the target 3.75V storage voltage, or half charge. I've also purchased another brand of Lipo and I'm seeing the same exact scenario.

    So, charge that Traxxas 7600 mah pack to 8.4v and I'm showing around 3800 mah put into the pack, thus backing up my thought that I'm at proper half charge when the truck becomes lethargic and unable to use high range gear.

    Is this situation typical? What are you seeing as far as voltage when your Lipo is barely moving your truck? It appears I can only access about half of the Lipo packs rated mah capacity, and this holds true in both the high dollar Traxxas pack and the low dollar China pack. It sure would be nice to be able to use the rest of the pack.

    In comparison: My 7.2V ni-mh packs that are rated at 4500 mah normally accept around 3800 mah from the MRC Battery Brain charger after a run to severe power loss, so they provide much more of the rated capacity to the truck.


    Sent from a Galaxy S3, far....far away.

  2. #2
    RC Racer
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    I'm surprised that no one has an opinion on this. I'm looking for someone to tell me that I'm seeing what is normal and that I don't have any sort of issue.

    Sent from a Galaxy S3, far....far away.

  3. #3
    RC Competitor
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    Maybe a faulty esc? Do u have a low voltage alarm by chance? You could possibly set the esc to nimh setting hook your lipos up and connect the lva to the battery on the bec side and see if the outcome is the same? Just a thought good luck


    Sent from my iPad using Tapatalk HD

  4. #4
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    I have a single LVA/voltage meter coming next week. I may try that. But I don't think the LVD of the ESC is (or should be) coming in at 3.75 volts per cell, i thought that Traxxas advertises it as shutting off at something like 3.3 volts?

    Sent from a Galaxy S3, far....far away.

  5. #5
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    Is it cold where you are?
    Whatever it is I just said... I could be wrong.

  6. #6
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    Quote Originally Posted by Jimmie Neutron View Post
    Is it cold where you are?
    Yes, around 15-25F, Pittsburgh, Pa.

    Sent from a Galaxy S3, far....far away.

  7. #7
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    Quote Originally Posted by Jimmie Neutron View Post
    Is it cold where you are?
    In my ignorance, I have no idea why your asking that or what your eluding to, but I suspect that your about to take me to school!

    Sent from a Galaxy S3, far....far away.

  8. #8
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    The bus just arrived! lol


    LiPo's hate the cold... I don't know the exact science behind it, but from what I can figure is that the C rating actually takes a large dive once they get cold. What is happening is that the power system is trying to pull more amperage than the cold LiPo's can handle, causing some wicked voltage dip.

    NiMh actually dislike cold too... but since they heat themselves up while you are using them they don't get as cold as cool running LiPo.
    Whatever it is I just said... I could be wrong.

  9. #9
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    So my half charged, but playing-dead Lipo packs..... would still run great for a long while if it were warm out?

    Sent from a Galaxy S3, far....far away.

  10. #10
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    More than likely, yes.

    Just in case you are wondering or thinking about it, it is not safe to lower the low voltage cutoff. The packs are actually dipping low enough to activate the alarm or LVC... lowering it will damage the pack. If voltage hits below the safe threshold even for a split moment, you are damaging the pack.
    Whatever it is I just said... I could be wrong.

  11. #11
    RC Racer
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    Quote Originally Posted by Jimmie Neutron View Post
    More than likely, yes.

    Just in case you are wondering or thinking about it, it is not safe to lower the low voltage cutoff. The packs are actually dipping low enough to activate the alarm or LVC... lowering it will damage the pack. If voltage hits below the safe threshold even for a split moment, you are damaging the pack.
    At the point that I'm at 3.75-3.8 volts, the truck can barely move so I limp it to me in low range and call it over.

    Sent from a Galaxy S3, far....far away.

  12. #12
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    I hope you have not drawn the packs down too far... you would have to be able to read the voltage as you drive to find out.
    Whatever it is I just said... I could be wrong.

  13. #13
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    Quote Originally Posted by larry0071 View Post
    I have a single LVA/voltage meter coming next week. I may try that. But I don't think the LVD of the ESC is (or should be) coming in at 3.75 volts per cell, i thought that Traxxas advertises it as shutting off at something like 3.3 volts?

    Sent from a Galaxy S3, far....far away.
    I had the same problem and question...so I called Traxxas and they said that the LVC is set to cut you off at 3.8 volts. I now shut off the LVC and rely on an alarm. I get much longer run times now

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