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  1. #1
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    Four cells, one plug.

    Ok, I have read about this in a few different threads, and the FAQ. I have seen the diagrams and already charge the 2s packs as a 4s so I'm all set with the wiring.

    Out of the info I've came across, I think that some ECSs can handle 4s on one plug with the other "shorted" and some ESCs can't. I think some have even not lasted on 3s.

    So here's my reason for this post. I have a 4s cut-off and have encountered the situation where one lipo get down to around .5 volts per cell lower than the other. I don't want to buy a 2s for the side that gets lower, so can I assume that wiring all four on one ESC plug and "shorting the other would create a situation where all four cells would share all the load equally? I can't see why not.

    Also, can anyone clarify if the EVX2 will handle the 4s on one side. I see lots of pictures depicting it, but most of the discussion is about it failing the esc.

    I read the thread about 5s on the EVX2 and DeWalt motor and it seams to be do-able. Just looking for something a little more definitive about this before I hook things up.

  2. #2
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    i run a dewalt motor on 2 4s in parrallel i have all four motor wires connecting from the esc to the motor and i have a jumper on one side of the esc and a y harrnes to run the two 4s on one set of original wires from the esc let me know if you need pics
    I was anti-obama before it was cool!

  3. #3
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    Quote Originally Posted by bmxdude
    i run a dewalt motor on 2 4s in parrallel i have all four motor wires connecting from the esc to the motor and i have a jumper on one side of the esc and a y harrnes to run the two 4s on one set of original wires from the esc let me know if you need pics
    Is that on the EVX2? Does it give you issues? Do you have/need a BEC? Would a BEC even help? What kind of temps at the ESC do you get after a long run?

    Thanks for the responce.

    Does anyone see a problem with a pair of 7cell NiMH on this type of set-up? Thats alot of volts right off the charger...

  4. #4
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    An external BEC would help, but I'm not sure the EVX2 needs help for the BEC... But it will help no doubt.

    I've seen lots of people use two parallel 4s packs on the EVX2 without issues.
    And in my thread about the 5s+14,4V Dewalt we established the EVX2 can handle two 5s parallel. The EVX2 thermals after 15mins though
    But we're not sure if it's the BEC overheating due to the 5s voltage, or the MOSFETs due to the high current the Dewalt draws...

    Anyway, if the Dewalt can handle 5s parallel, it will be able to handle 7cell nimh parallel. The nimh does drop in voltage fast, so it's comparable to 4s voltage-wise
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  5. #5
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    yes the evx2not many issuses any more as i have eliminated any them like glitching and very hot temps,

    i bought the truck used wired for 2 4s and a dewalt already installed,i was having some glitching so i put the third capacitor on now i dont have any issuses my heat problem i jyst resolved yesterday (after having the truck for 3 monhs. i problem was the truck had the2 speed kit, but the previous owner made first gear normal stock gearing and second over drive and with iut realizeing it i was driving in over drive the whole time so i put back in first(stock gearing) and a 20t pinion and a 58t spur and it has great tourqe and ood top speed whren i need it!! but i plan on getting a bec for even lower temps
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  6. #6
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    Quote Originally Posted by bmxdude
    yes the evx2not many issuses any more as i have eliminated any them like glitching and very hot temps,

    i bought the truck used wired for 2 4s and a dewalt already installed,i was having some glitching so i put the third capacitor on now i dont have any issuses my heat problem i jyst resolved yesterday (after having the truck for 3 monhs. i problem was the truck had the2 speed kit, but the previous owner made first gear normal stock gearing and second over drive and with iut realizeing it i was driving in over drive the whole time so i put back in first(stock gearing) and a 20t pinion and a 58t spur and it has great tourqe and ood top speed whren i need it!! but i plan on getting a bec for even lower temps
    I've searched for the best BEC around, and have found the 3A-5A switching BEC (standard EVX2 BEC is 2,5A) from ********* is the best. It's only 8$
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  7. #7
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    alright thanks any lnks?
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  8. #8
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    Should be this little hog right here.

    Linky.

  9. #9
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    Quote Originally Posted by koolwhipman
    Should be this little hog right here.

    Linky.
    That's it.

    Let us know howmuch the temps drop!
    Your post was edited for inappropriate language.

  10. #10
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    haha am i the little guiniea big were testing on? thge real question is can i fit that and my lvc in the redciver box keeping everything waterproof? theres a little space left in the box but i dont know if theres enough for that too?
    I was anti-obama before it was cool!

  11. #11
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    Well I hooked up my pair of 7 cells to the one plug and capped the other, yada yada, ya know. It ran as usual for about two minutes and then quit. I unplugges the batts and plugged them in the regular way and it worked fine.

    When it quit I had nothing, throttle or steering. Hmmm...

  12. #12
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    See here:
    http://monster.traxxas.com/showthread.php?t=460778
    and here:
    http://monster.traxxas.com/showthread.php?t=458760

    I have posted this a few times. Some people may be getting lucky running higher voltage on the BEC side, but it really is just luck.

    The BEC is designed to run off of 1 battery pack and is expecting 7.2 to 8.4 volts.By doubling up the volts on the BEC side of the ESC, your just asking for trouble.
    If Traxxas had a high voltage BEC inside the ESC, I dont think that they would have wired it to only one side of the battery inputs, so it only used one battery.

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