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  1. #1
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    Lipos and low volts???? Bad?

    Okay short version. My buddy has the same setup as my summit. (dewalt 14.4, 2s 5200 lipos) Yet he would always get longer run times I never understood it till today. He dosnt run a lipo cut off like mine. I have the novak 2s. He runs nothing, Runs the batteries till they are done then puts new ones in. Goes home and charges them up..... HOW can he be doing this????? How bad is this for the batts and he has done this 25+ times. I looked at the packs and no puffing or anything....... Has anybody else done this? Please let me in on this sort of thing...
    Thanks
    Wouldn't you like to know...

  2. #2
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    But when is he disconnecting ?
    when it just slows down , or when it wont go any more ?


    I have been running with no cut off , and finally got a Novak cut off installed yesterday .
    how , I use a eos sentry and check the voltages once every 5 to 10 minutes depending on what kind of driving.
    after awhile, i just know when to stop. and its usually around 20 - 30 % left in the tank.

    but i notice I don't go until that novak cuts off, in fact I have yet to see the blinking light or the throttle deal.
    Why, Because i stop at 30 to 20 % like i always do with lipos . that novak wants to cut off way low , which yo wont see me do. to me its cut off is way to low , for me personally .

    anyway if the lipo is cool (which it probably is , it probably will not puff ). but if taking that thing really low , I would not recommend if you want them to last , and keep there punch longer. Older types (10 and 15 c ) probably would puff, but now days there pretty good even the cheapo ones, if using the new Formulas about 25c and higher . might be possible His packs have a Circuit to keep them safe , I know some brands have a circuit for the charging side (electrifly or something).

    but you still cant poke them (they don't like that at all) , well maybe the sky's can tolerate it.

  3. #3
    RC Turnbuckle Jr. jamann's Avatar
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    I use a alarm on the bec side pack when crawling i can keep going for a while after the first beep as it's not drawing huge amp's once it is getting low beep and flashing blue then when it's time to stop ,flashing red and the alarm goes nuts.so i can in theroy get about a hour a set of cheapo 5000 30c packs
    Mountains cant stop me
    they have tried

  4. #4
    RC Champion
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    Running lipos down past the point where the charger returns more than 80% of the packs capacity will greatly lessen their life .... in "most" lipos. Some lipos (like Kongs) can be run lower with no problems. Check manufacturers specs!!!

    If run way low "many" chargers will not start a charge on them .... and forces you to pre charge in NiMH mode until you get the volts up.

    THIS is exactly why I prefer a fully voltage adjustable alarm (2.0v to 4.0v) like the Chargery BM6. I use a much higher voltage alarm setting when crawling since their is less load. Personally I like to have my packs at 3.6 - 3.7v per cell after resting when done using.
    I make tap adapters and power harnesses.

  5. #5
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    Bob

    I like the specs of that 2-4.2 volts adjustment range . http://www.rcaccessory.com/bm6.aspx

    do you know what balance taps it will fit , or does it matter.

    wish i knew about these earlier. errrr. the novak is coming out soon, all that work for nothing

    Thanks

    PS I notice by Handle you must Fly Helis, can you hear that Bm6 flying ?
    might get these for my helis too.
    Last edited by VonGearStripper; 01-10-2011 at 01:04 PM.

  6. #6
    RC Turnbuckle Jr.
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    Quote Originally Posted by choppermech11@m View Post
    Okay short version. My buddy has the same setup as my summit. (dewalt 14.4, 2s 5200 lipos) Yet he would always get longer run times I never understood it till today. He dosnt run a lipo cut off like mine. I have the novak 2s. He runs nothing, Runs the batteries till they are done then puts new ones in. Goes home and charges them up..... HOW can he be doing this????? How bad is this for the batts and he has done this 25+ times. I looked at the packs and no puffing or anything....... Has anybody else done this? Please let me in on this sort of thing...
    Thanks
    He either uses The Force, or he is extremely lucky his truck isnt a molten blob of plastic- I too would ask when he stops running though, and what the voltages are when he does; if he isnt aware that he should be using an LVC with lipos, then make him aware for his own sake...
    Keeping the Mods busy is my specialty...

  7. #7
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    Quote Originally Posted by ArmyofDarkness View Post
    He either uses The Force, or he is extremely lucky his truck isnt a molten blob of plastic- I too would ask when he stops running though, and what the voltages are when he does; if he isnt aware that he should be using an LVC with lipos, then make him aware for his own sake...
    I did, I told him to go and buy a novak lipo cutoff. I honestly had no clue he wasnt using one. Mine is tucked in the reciever box. We have run our trucks now 25+ times. He told me that he has run the batteries that was the whole time. He just puts new ones in when the truck stops..........

    When you said "molten blob of plastic" Refering to getting too hot, or exploding?
    Wouldn't you like to know...

  8. #8
    RC Turnbuckle Jr. jamann's Avatar
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    When lipos get hot they swell and if they swell to the point of rupture a good sized fireball is going to happen and if it's in his truck at the time the molten blob o plastic will be the end result. when they go it releases a lot of energy.Check out you tube keep in mind the ones on you tube are done on purpose, not real smart but hey we can't all be rocket scientists otherwise who'd flip our burgers
    Mountains cant stop me
    they have tried

  9. #9
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    Uses the Force Good one.

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