Lipo 7.2 dumb question

Discussion in 'Electrical & Radio' started by Sinkazuki, Feb 15, 2019.

  1. Sinkazuki

    Sinkazuki Active Member

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    Is there a way to reduce voltage of the 7.2 2 cell pack down to 6 volt WITHOUT using an esc?
    I like simple . Probably a dumb question.
    Thx
    Randy
     
  2. bsgkid117

    bsgkid117 Vendor

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    Two options I can think of off the top of my head are to just use the ESC's BEC, they are very simple and work pretty flawlessly.

    Second option is to just use a dedicated receiver battery.
     
  3. BigGunJeff

    BigGunJeff Well-Known Member

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  4. SnipeHunter

    SnipeHunter Well-Known Member

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    6v voltage regulator

    How much current are you planning on pulling? That makes a huge difference on what you actually want to buy.
     
  5. WillCover

    WillCover -->> C T D <<--

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    Voltage drop across a diode is .7v ,x2 ~1.4v
     
  6. Nate G

    Nate G Well-Known Member

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    As SH queried, how much current draw do you need?
    there are several ways to achieve a lower voltage but the best way will depend a little on power needs.
     
  7. Sinkazuki

    Sinkazuki Active Member

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    I don't know how many amps I draw.
    The setup is basic cruiser. always 6v running two 360 motors direct.
    The diode idea seems easiest.
    Does it just go across the battery leads?
    Thx
    R
     
  8. WillCover

    WillCover -->> C T D <<--

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    cir.PNG maybe some one else can suggest the correct types to use, I only used it on a low current pump indicator motor .
     
  9. SnipeHunter

    SnipeHunter Well-Known Member

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    Can you just use 7.2V? or get a 6V pack?

    If you just need 6V for one part can you run that at 6V and everything else at 7.2V?

    Even if you just want to use diodes you need to have some sort of idea on current draw so you can size the diodes correctly. Also if you're drawing any significant current you'll probably want some sort of heatsink for them since they'll be burning a bit of energy.
     
  10. Sinkazuki

    Sinkazuki Active Member

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    I'm running 6v nimh packs now but they're getting old.
    It seems like all the cool guys are going with lipo.
    I was hoping there was a simple reostat or potentiometer to bring the lipo down to six.
    I know, esc is the proffered way to do it but I'd have to get a new radio and there's always the temptation to cheat.
    Example,
    "Hey! That 28 second Fuso is catching my 24 sec tiger! I'm going to speed up!
    Randy
     
  11. djranier

    djranier Well-Known Member

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    Fuso is 26 sec. At this last Nats a Allied pre-dred was running down the 22 sec light cruisers, that's a 6 sec difference, your 2 second should not be a issue then.
     
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  12. bsgkid117

    bsgkid117 Vendor

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    Why would you need a new radio? And the potential to cheat is always there. In order to speed up with an ESC and a modern radio youd have to change the endpoints in the settings mid battle. Not super easy or fast. And cheating is still a personal moral kinda choice. Locks keeping honest people honest, etc.
     
  13. Sinkazuki

    Sinkazuki Active Member

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    My radio is a dx5, I don't think the analog endpoint adjustments work on an esc. I could be wrong.
    I got an old esc somewhere, I'll try it.

    Maybe I'll use a hacksaw to take 1 inch off a lipo cell.
    I'll let you guys know later if it works.
    Randy
     
  14. Kotori87

    Kotori87 Well-Known Member

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    Analog endpoint adjustments work just fine with an ESC. I used to use them all the time, before I switched to 2.4ghz digital radios. Very handy for setting ship speed, and making sure your servos move just enough to press the MAV's instead of stalling.

    Good luck! I hope that works.
     
  15. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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  16. SnipeHunter

    SnipeHunter Well-Known Member

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    They did it all wrong! You obviously need to use a non-conductive cutting tool and be mindful not to create any internal shorts when cutting part off of a battery to reduce the voltage. Duh...

    In all seriousness there are ample ways to cheat in this hobby if you're so inclined, in the end it's up to you. If you see a 28 sec ship running 22 sec and you don't call them out on it you aren't helping the situation, speed testing is pretty quick/easy. If you do and the CD doesnt want to enforce the rules then...well..pick a better CD next time.
     
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  17. Sinkazuki

    Sinkazuki Active Member

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    Just got out of the hospital, they were able to reattach my left ear. Now we just have to fix my neighbor's fence and find or replace his cat.

    Maybe the easy answer is to find slower motors in a 360 size