Results 1 to 16 of 16
  1. #1
    RC Competitor
    Join Date
    Oct 2002
    Posts
    75

    UBEC install experts?????? On EVX-2 ?????

    hello guys,
    I bought a UBEC to power up my 7 servos on my Summit.

    I know I would disconnect the RED wire on my ESC (EVX-2) when plugging into the Reciever,
    ok I've done that so far...........

    .....now I plug in my new UBEC into the batt port of my Reciever,

    my question is:

    where do I plug the UBEC in for power?????
    I know its on one of the Two 2s Lipos connecting to the ESC,
    but which one?

    someone told me on the forum that one of the batteries will be drained less b/c one powers the motor, other other 2s Lipo powers the servos.....

    which battery shall I piggy back for my UBEC?

    I dont know which one to tap into?

  2. #2
    RC Qualifier
    Join Date
    Dec 2009
    Location
    Alberta, Canada
    Posts
    553
    You solder it into one of the battery terminals on the esc. Doesn't matter which one. I have a castle BEC on my CR-01 crawler.
    SUMMIT- DeWalt, 4S
    SUMMV- 3S
    MERV- 3S

  3. #3
    RC Champion
    Join Date
    May 2009
    Location
    Southeast PA
    Posts
    1,931
    If a stock EVX2 then the battery plug with the red tag is the BEC side pack .... but you are disabling it so both packs would drain the same.


    What voltage are you planning to feed your UBEC .... 2S or 4S?

    You could feed your UBEC from the balance tap on your lipo with the right adapter.

    Just remember .... the EVX2 is internally wired for series and when both 2S packs are pluged in to the stock EVX2 wiring you no longer have two 2S packs ...you have a 4S pack.

    Use a meter and find the common ground and power to find the internal series connection. Don't go by this or any other drawing!!



    Electrically you have a lot of options by eliminating the BEC circuit .... like running on two 4S packs in parallel .... but you REALLY need to understand the INTERNAL SERIES wiring of the EVX-2 to avoid a bad mistake.

    Bob
    Last edited by Hughes500Bob; 08-06-2010 at 09:46 AM.
    I make tap adapters and power harnesses.

  4. #4
    RC Competitor
    Join Date
    Oct 2002
    Posts
    75
    hughes500Bob
    .....I didn't know that....
    this is what I bought....
    http://cgi.ebay.com/ws/eBayISAPI.dll...#ht_2715wt_907

    .....
    so what you are saying is that it doesn't matter what side of the battery pack that I'm using to piggy back the UBEC.

    ok , I got that part....

    again,,,,I'm still using the stock ESC (EVX-2), I don't know what you are saying by 4s Parallel?

    I have Two 2s-5000mah Packs running right now....all I wanted to do was power the servos with a UBEC.
    I want to keep things simple and get very high run times....thank Bob :-)
    Last edited by rclab1; 08-06-2010 at 10:32 AM.

  5. #5
    RC Qualifier
    Join Date
    Dec 2009
    Location
    Alberta, Canada
    Posts
    553
    Solder to a pair of the esc battery terminals. Doesn't matter which one as stated already.
    SUMMIT- DeWalt, 4S
    SUMMV- 3S
    MERV- 3S

  6. #6
    RC Competitor
    Join Date
    Oct 2002
    Posts
    75
    ok, I will solder the UBEC on a pair of the ESC battery terminals.

    I was going to plug it into the balancing port on one of the two 2s-5000mah packs, but I guess it would be easier to just solder onto a pair
    of ESC battery terminals.....

  7. #7
    RC Competitor
    Join Date
    Oct 2002
    Posts
    75
    The CastleCreations UBEC.....
    its adjustable....

    how do you adjust that?

    and I have a total of 7servos....going on 8 servos (working steering wheel)

    what Voltage should the CCUBEC be in???????

  8. #8
    RC Champion
    Join Date
    May 2009
    Location
    Southeast PA
    Posts
    1,931
    Product Name: 5A U-BEC UBEC Input 9-30V 3-8S Lipo battery 8-24Nimh R7

    For: 9-30V 3-8S Lipo battery 8-24Nimh

    1.input voltage:5V

    2.continuous current:5A

    3.max output current:>5.8A

    If I'm reading the specs .... I hope #1 is output voltage 5V .... and it is saying 3S to 8S lipos for input... so you'd have to use the ground on the BEC side plug and the power off the other and input 3S or 4S somehow. Personally I'm a bit suspect of a $3 UBEC making those claims!!!

    QUALITY PRODUCTS = http://www.dimensionengineering.com/productpage.htm

    I'd personally want 6 volts if you have high torque servos. Here is where a data logger or watt meter would be good to see what the true demand is.

    The EVX2 ain't the greatest ESC (no offense Traxxas). Ever consider upgrading?

    Kershaw Designs has a 4 amp BEC that's 7.4 to 22.2 input and 5V or 6V selectable output for $11.99 ..... might fit your application well??? Look around at other ESC and motor combos while your there!!!

    Taking power for 2S from a balance tap is EASY:


    Your FPV system looks GREAT! IMO look closely at the kershaw designs BEC and forget that $3 unit!

    Bob
    Last edited by Hughes500Bob; 08-06-2010 at 10:45 PM.
    I make tap adapters and power harnesses.

  9. #9
    RC Competitor
    Join Date
    Oct 2002
    Posts
    75
    Hughes500Bob

    thanks for the inspection....
    I will not use that $3.00 BEC that I bought....it is not worth risking it.....
    can you give me the Links to the BEC you prefer....
    again, I'm using Stock everything and I use a Two 2s-5000mah Lipo packs.

    thanks

    p.s. that Link you gave up above had serveral BEC..... which one is the simplest.....

  10. #10
    RC Champion
    Join Date
    May 2009
    Location
    Southeast PA
    Posts
    1,931
    http://www.kershawdesigns.com/

    Products > Brushless speed controlers > Kershaw Designs Gen II ESCs > 4A BEC

    As far as the Dimension Engineering products .... with your FPV application I would go with the Sport BEC .... and input 4S voltage with 6V output selected. This should give you plenty of juice to run all your servos.

    ALL Dimension Engineering products IMO are top notch. I have their voltage regulator installed in my DX-7 Tx.
    I make tap adapters and power harnesses.

  11. #11
    RC Competitor
    Join Date
    Oct 2002
    Posts
    75
    thanks Hughes500Bob,
    I just bought the UBEC that you gave up above...

  12. #12
    RC Champion
    Join Date
    Jan 2008
    Location
    USA
    Posts
    1,514
    The Castle BEC would be more than sufficient as well. To program it up though, you also need to have the Castle Link to connect to the computer. It programs through the servo wire that goes into your receiver to power everything up.
    You definitely want 6V on your BEC as the stock ESC puts out 6V from the internal BEC. Otherwise, you'll lose out on some torque from your steering servos.
    As to which battery to put the input on, it doesn't matter. Just remember that whichever one you put it on will drain faster than the other unless you do it on the 4S setup and connect to the proper leads on the ESC (you'll need to measure like others have suggested to find where to connect to).
    Good luck and hopefully you'll get that other one sold!

  13. #13
    RC poster
    Join Date
    Mar 2010
    Posts
    7
    Can the stock Traxxas Receiver be powered at 7.4v?

    The reason I ask is that there are some servos now that are optimized for 6.0 to 7.4v (whereas before, spec ratings were 4.8 to 6.0v).

    I know the servos can be powered to 7.4v, but the BEC would also be powering the receiver, right? So, is it safe at 7.4v?

  14. #14
    RC Champion
    Join Date
    Aug 2009
    Location
    Spruce Grove, Alberta
    Posts
    1,552
    Quote Originally Posted by Alfalfameister
    Can the stock Traxxas Receiver be powered at 7.4v?

    The reason I ask is that there are some servos now that are optimized for 6.0 to 7.4v (whereas before, spec ratings were 4.8 to 6.0v).

    I know the servos can be powered to 7.4v, but the BEC would also be powering the receiver, right? So, is it safe at 7.4v?
    Or could anyone explain how to configure the system to power individual servos to 7.4? If its even possible?
    http://traxxas.com/forums/showthread.php?536733

  15. #15
    RC poster
    Join Date
    Mar 2010
    Posts
    7
    Quote Originally Posted by quadiak
    Or could anyone explain how to configure the system to power individual servos to 7.4? If its even possible?
    quadiak brings up a good point! I'm so used to my other truck (which only has the ESC and ONE [steering] servo.

    I forgot about the other servos that the Summit has!

    Maybe I should just stick to 6.0 volts... (was hoping to use 7.4v since some steering servos (such as the newer Hitec ones) are rated to 7.4v, and therefore have slightly more torque and faster response).

  16. #16
    RC Champion
    Join Date
    Aug 2009
    Location
    Spruce Grove, Alberta
    Posts
    1,552
    brasher let the secret out. lets hope it works.
    http://monster.traxxas.com/showthread.php?t=533714
    http://traxxas.com/forums/showthread.php?536733

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •