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  1. #1
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    BEC in telemetry ports?

    I'm going to upgrade my current 2075's to better servos(They both stripped, as you all know). In order to get my money's worth, I need to put a BEC in (these servos draw more than the stock 2.5 amps). The problem is that there are no open ports on my receiver other than the telemetry ones. Will these ports still work?

  2. #2
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    Just pulled the receiver out and apparently the telemetry ports do not work. I checked contact between channel 2 and the the telemetry Port. No connectivity. I figured out a way to get it to work though.

  3. #3
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    How did you get it to work?

    One option you could use is to run the BEC power to the servos directly and run only the signal leads back to the receiver. And you could leave the rest of the RX and all other servos powered off of the EVX-2 internal BEC. This would effectively remove the high power servo load from the RX without needing any extra RX ports. This way you could even run your BEC at higher voltage (6.0V or 7.4V for some servos) and keep the rest of your RX and other misc stuff at the stock 5V

    Unless I'm blanking and totally forgetting something (it's really late for me right now), that should work.

    Not that it matters anymore as you seem to have it figured out.
    Last edited by larsen8; 04-14-2020 at 01:59 PM.
    Why can't other people share my opinions?

  4. #4
    RC Champion grizzly03's Avatar
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    Quote Originally Posted by larsen8 View Post
    ... at the stock 5V...
    The BEC voltage of Traxxas ESC's are 6v on all the ones I own and are suppose to be a 6v output not 5v.

  5. #5
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    Quote Originally Posted by grizzly03 View Post
    The BEC voltage of Traxxas ESC's are 6v on all the ones I own and are suppose to be a 6v output not 5v.
    Correct you are. For some reason I was thinking 5V. It was late last night.
    Why can't other people share my opinions?

  6. #6
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    Hey gang just wanted to let you know i tried the cc 10a bec in the rpm slot in the reciever box and that will set you back $40 in a new reciever box. Just heads up i got my summit back up and running yesterday with the new reciever. But something is not right with the steering. I got 2x 1210sg savox servos in the car now but they glitch out very often. Dont center themselves and steering is a bit laggy. I connected the bec directly to the servos and ran the 2 signal wires from the servos back to the reciever box, everything else is stock. Anyone got any ideas?

  7. #7
    RC Champion grizzly03's Avatar
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    Quote Originally Posted by TheBuG View Post
    Hey gang just wanted to let you know i tried the cc 10a bec in the rpm slot in the reciever box and that will set you back $40 in a new reciever box. Just heads up i got my summit back up and running yesterday with the new reciever. But something is not right with the steering. I got 2x 1210sg savox servos in the car now but they glitch out very often. Dont center themselves and steering is a bit laggy. I connected the bec directly to the servos and ran the 2 signal wires from the servos back to the reciever box, everything else is stock. Anyone got any ideas?
    It might be the servos. Together they could be drawing more than the 10amps the CC BEC can handle. Try using only one servo. Savox servos are known to be power hungry.

  8. #8
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    Quote Originally Posted by TheBuG View Post
    Hey gang just wanted to let you know i tried the cc 10a bec in the rpm slot in the reciever box and that will set you back $40 in a new reciever box. Just heads up i got my summit back up and running yesterday with the new reciever. But something is not right with the steering. I got 2x 1210sg savox servos in the car now but they glitch out very often. Dont center themselves and steering is a bit laggy. I connected the bec directly to the servos and ran the 2 signal wires from the servos back to the reciever box, everything else is stock. Anyone got any ideas?
    Not sure if I'm understanding this correctly but you need the signal wire and the ground in the rx box. Check out this hook up I've done with mine it shows how to connect everything.
    https://forums.traxxas.com/showthrea...rvos-and-tires

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    Rain dawg, thanks for the reply. I tried disconnecting one servo and the steering became perfect, so then my brain started working, (Yeah i was suprised it started working) is it because i dont have connected the black ground wires from the servos to the reciever box or just because the bec dont output enough power. I wonder .... as long as i dont connect any red/positive wires from the servos/cc bec to the reciever box i should be fine right?

  10. #10
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    Check out the thread I linked above and it shows how the adapter is wired and how it connects to the rx and the servos. The bec your using is more then enough power to run those servos if you connect directly to the batteries and bypass the rx and only run the signal and ground from the servos into it.

  11. #11
    RC Champion grizzly03's Avatar
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    Check the specs on the servos. They need too much power. At 6v they draw 6amps and at 7.4v they draw 7.4amps. When you have two now double the amps. It would be 12amps at 6v and 14.8amps at 7.4v.

  12. #12
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    Quote Originally Posted by grizzly03 View Post
    Check the specs on the servos. They need too much power. At 6v they draw 6amps and at 7.4v they draw 7.4amps. When you have two now double the amps. It would be 12amps at 6v and 14.8amps at 7.4v.
    LOL that's crazy, good catch on the amp draw. He still only had the signal connected and not the ground so maybe it'll work if the signal and ground were connected. Worth a try at this point.

  13. #13
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    Grizzly, good point. Its tempting to buy a more powerful bec but rain dawg has it working so i guess ill try to connect the black wires to my reciever box and see if that helps.

    Rain dawg, yeah thanks for the link to your thread. Im a bit worried about connecting more wires to my reciever since i fried it once. Will the black wires help, i wonder.

    Another thing to note is that at one time i will go brushless with a programmable esc with integrated bec that is powerful enough for my servos. Like cc mamba motor.

    Another idea from a friend of mine that also bought a summit that is gonna upgrade the same parts as me is that i could connect 1 servo to the evx2 esc and have the other one go through the cc bec. But then they wont run on the same voltage so that will make one go faster then the other and that might strain the slower one

    Thanks for the reply btw. Have been checking youtube for help but sometimes when you look for somerhing real specific it can be real hard to find the answer out there.

    I feel i came to the right spot here at traxxas forum

    Cheers from Norway
    Last edited by TheBuG; 05-09-2020 at 12:40 PM.

  14. #14
    RC Champion grizzly03's Avatar
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    Quote Originally Posted by TheBuG View Post
    ...Another thing to note is that at one time i will go brushless with a programmable esc with integrated bec that is powerful enough for my servos. Like cc mamba motor...
    Check the ESC internal BEC specs of what ESC you are looking at. Most are not high enough. The CC MambaMonsterX is only rated at 8amps. If you really want those two servos, purchase a bigger BEC.

    Another idea from a friend of mine that also bought a summit that is gonna upgrade the same parts as me is that i could connect 1 servo to the evx2 esc and have the other one go through the cc bec. But then they wont run on the same voltage so that will make one go faster then the other and that might strain the slower one
    Don't do it. Not a good idea.

    I feel i came to the right spot here at traxxas forum
    Most here will give you sound advice. Good community.

  15. #15
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    If you wire up the bec as I did in my thread and connect both servos as I did you should'nt have any problems but like grizzly stated your only using a 10 amp bec for those servos I'm using a 15 amp bec.

    You already have the electronics that your working with so you should try as I suggested and if that doesn't work (I beleive it will) then switch servos or buy a bigger bec. At this point if you don't follow the pics in my post your still where you are, and even if you switch esc's later the Traxxas rx's only take 6v so you would need to upgrade tx and rx.

    The servos need a ground for them to work so yes put the black and yellow in the rx, it will not harm or fry your rx if you haven't added any hot wires (red).
    Last edited by Rain Dawg; 05-09-2020 at 01:30 PM. Reason: add

  16. #16
    RC Champion grizzly03's Avatar
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    Quote Originally Posted by Rain Dawg View Post
    ...The servos need a ground for them to work so yes put the black and yellow in the rx, it will not harm or fry your rx if you haven't added any hot wires (red).
    +1
    Grounds never hurt, it's that dang red one that gets you!

  17. #17
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    Quote Originally Posted by grizzly03 View Post
    +1
    Grounds never hurt, it's that dang red one that gets you!
    The servos has ground/black from the bec so i dont see why i would need to connect the black wires to the reciever. they both come from the same source, the battery

    I'll see what i end up doing. but i like the idea of spending more money on my rc so :P bigger bec and waterproff would be nice :P

  18. #18
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    Quote Originally Posted by grizzly03 View Post
    +1
    Grounds never hurt, it's that dang red one that gets you!
    Yup lol or plugging them in backwards haha

  19. #19
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    Quote Originally Posted by TheBuG View Post
    The servos has ground/black from the bec so i dont see why i would need to connect the black wires to the reciever. they both come from the same source, the battery

    I'll see what i end up doing. but i like the idea of spending more money on my rc so :P bigger bec and waterproff would be nice :P
    Before I did mine I researched the heck out of it reading lot's of different post's in different forums and it all comes back to it needs a ground with the signal wire, it's one little wire and if you put it in there and it works like mine then you save money lol.

  20. #20
    RC Champion grizzly03's Avatar
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    When you add the extra ground wire it will eliminate possible issues with a "floating ground" or "feedback voltage".

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    Quote Originally Posted by grizzly03 View Post
    When you add the extra ground wire it will eliminate possible issues with a "floating ground" or "feedback voltage".
    I've been running two different summits for quite some time now with two different external BECs and steering servos with just a signal wire (no ground) running back to the RX. It works just fine but yes, you can run an additional ground to the RX. Doesn't hurt and will indeed eliminate all possibilities of a floating ground. I don't know that I would necessarily consider it best practice. More of an additional caution.
    Why can't other people share my opinions?

  22. #22
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    Also, for those interested in something beefier than the 10amp CC BEC, which is running a single Ecopower servo in my wife's Summit currently and is still barely passable, there are a couple other good options out there. CC makes a couple of bigger brothers (which carry a much higher price), one in a 20amp and another in a 15amp with a cool waterproof box around it. But they are a bit spendy. If you are like me and like your pocket book to stay full, check out YEP 20amp BEC. Waaaay cheaper. That's the one I run in my Summit. Pretty feature heavy and has been serving me well for years now with zero issues.
    Why can't other people share my opinions?

  23. #23
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    "When you add the extra ground wire it will eliminate possible issues with a "floating ground" or "feedback voltage"."

    Sounds interesting! A glimmer of hope thanks for all the replies. Ill write back once i have tried the black wire!

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