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external bec +esc bec

ferp420

who did i wanna be again
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Jan 9, 2016
Messages
4,902
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california under the rock im crawling on
I had a thought about using becs i know your saposed to cut the power lead from the esc to the reciver but could a person just add a diode to both powerleads and have more available juice if both sorces are running the same voltage so the external puts out 3amps the esc puts out 2amps so i should have 5 amps to play with right or am i way off at one point in time i bought a lot of cheap becs so im trying to use them up or i would just get a more powerfull one but i dont think i need more than 3 for the servo but i do want to add some lights i know i can wire them seperitly but just woundering if i can run them in seiries
 
Castle bec is $20 and it's 10 amps which will drive ever servo I can think of. Why would I mess with diodes and possibly burn up more expensive electronics.
 
I had a thought about using becs i know your saposed to cut the power lead from the esc to the reciver but could a person just add a diode to both powerleads and have more available juice if both sorces are running the same voltage so the external puts out 3amps the esc puts out 2amps so i should have 5 amps to play with right or am i way off at one point in time i bought a lot of cheap becs so im trying to use them up or i would just get a more powerfull one but i dont think i need more than 3 for the servo but i do want to add some lights i know i can wire them seperitly but just woundering if i can run them in seiries

Castle bec is $20 and it's 10 amps which will drive ever servo I can think of. Why would I mess with diodes and possibly burn up more expensive electronics.

For the effort, it would be simpler, easier more reliable and safer to do like VooDoo said and just run a 10A BEC, remove the red wire and call it done.

Technically your idea would work, but you'd wire them in parallel, not series. But, you'd need to match the voltages, and that may not be possible.

When I do this, I don't actually cut the red wire, but pull the pin out of the connector, isolate it with heat shrink, and tape it back to the ESC cable. This allows me to easily undo this mod if I use this BEC for another project and don't need to run a BEC.

Another way around this whole mess is to get an ESC with a beefy BEC built in, like a Mamba-X.
 
I had a thought about using becs i know your saposed to cut the power lead from the esc to the reciver but could a person just add a diode to both powerleads and have more available juice if both sorces are running the same voltage so the external puts out 3amps the esc puts out 2amps so i should have 5 amps to play with right or am i way off at one point in time i bought a lot of cheap becs so im trying to use them up or i would just get a more powerfull one but i dont think i need more than 3 for the servo but i do want to add some lights i know i can wire them seperitly but just woundering if i can run them in seiries


A diode does block voltage from flowing backwards, but it isn't perfect. It has a voltage drop(normally 0.4-0.7 volts) so you would need to compensate for that. I wouldn't recommend trying that as a setup, it would still likely have some weird effects on the stability of the output voltage that might damage your electronics. If you don't want to cut the wire, I would get a 3" servo extension and pull the red wire from both plugs. That way you can easily switch back to it if you need to and, if it is a Castle controller, still allows you to easily plug it into a USB Castle Link.
 
My thoughts were considering the problem in electronics people get from ground wires looping or not looping I certainly think combining power wires would have more issues. But I am not an electrician or have any actual reasoning of why it wouldn't work, other then to say these electronics are already finicky enough, so don't give them an extra reason to complain. It is an interesting idea, but i believe the chances of you burning out a more expensive component, then replacing it as well as purchasing a $20 BEC that you could have just done in the beginning, are too high.
 
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Ive run both esc bec and a external bec with no diodes with out issue not for long but still nothing burned out this is the same set up same servo and esc only this build will have more lights if i add up all these electronics it might
add up to $25 so not a big deal if something frys but still its easy enuff to just wire everything seperetly
 
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Ive run both esc bec and a external bec with no diodes with out issue not for long but still nothing burned out this is the same set up same servo and esc only this build will have more lights if i add up all these electronics it might
add up to $25 so not a big deal if something frys but still its easy enuff to just wire everything seperetly
Another thought, if the built-in BEC is meeting your needs already, why not just wire the lights and other extra stuff directly to the external BEC?
Then you should have no uses whatsoever.

Sent from my Pixel 2 using Tapatalk
 
maybe ots the lack of sleep but im a little lost what you are looking to do.

i myself used the esc to power the rec and feed my servos with only the signal wire going to my servos. i power my two servos with two different bec's so i can over voltage one and just feed the other with the recommended voltage.
 
I'm the same as mach2nh. The new Flysky receivers for the Noble don't like 7.4 volts, so I use the esc bec to power the receiver and the bec just the servo. I don't run lights or winch though. If there is any glitching of the servo, It can help to run a ground wire from bec to receiver.
 
BEC bypass splitters are readily available so you don't need to cut/remove the "red" wire. Why make more work for yourself when all this stuff is readily available and cost effective? I mean, I'm all for innovation and I dig "home brewed" stuff. But why risk burning your electronics up when the cost for proven, tested products is so affordable?

10amp Castle BEC = $20
Bypass = $6-$10
 
BEC bypass splitters are readily available so you don't need to cut/remove the "red" wire. Why make more work for yourself when all this stuff is readily available and cost effective? I mean, I'm all for innovation and I dig "home brewed" stuff. But why risk burning your electronics up when the cost for proven, tested products is so affordable?

10amp Castle BEC = $20
Bypass = $6-$10

I would argue against using ready-made products like that. If you are going to diddle with your electronics in this way it is a VERY good idea to know what you are doing and why it is being done. Buying a magic connector that takes away from that process can lead to problems down the road. Also, getting a bypass splitter adds two more connectors into your wiring, which introduces two power places for signal loss and failure.
 
I would argue against using ready-made products like that. If you are going to diddle with your electronics in this way it is a VERY good idea to know what you are doing and why it is being done. Buying a magic connector that takes away from that process can lead to problems down the road. Also, getting a bypass splitter adds two more connectors into your wiring, which introduces two power places for signal loss and failure.

If by “magic”, you mean they’ve taken care of eliminating the red wire for you, then yes, it’s “magic”. Additionally, using this set up certainly does not preclude someone knowing what they’re doing. As far as the additional connections, signal loss, this is a complete non-issue.
 
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