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bifft it

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at what point do we decide how much servo is too much for steering?
right now in 2 of my trucks(X and flux) i run Savox SC0251MG [email protected] and in the other 2 (XL and shelfqueen) i run savox SC 1267SG [email protected] or [email protected]
as throttle servos I run HPI SF-50 in all but the shelfqueen

I want to make the jump to all 7.4v so i can use LiPo receiver batteries and cut down on items i carry with me for the hobby as i will be living in a camper again this summer.

here is what i am looking at.
Savox SV1270TG [email protected] for steering. too much? isn't going to rip the steering out my trucks, is it?
savox SV1268SG [email protected] for throttle. too small?
 

HPIguy

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End point adjustments, learn it, love it, use it. :D I run a 1270TG on my Wraith after it ate a 7950 one day. Once you have that kind of TQ and speed, you'll be forever spoiled, and never go back. I've actually had the Wraith move smaller rocks if the wheels are up against them. LOL I also run a 1231SG in the comp rig, and it's plenty capable as well. Only thing I will mention, if you're going to high end servos, you will need a BEC, especially for Savox as they are known to be power hungry.
 

bifft it

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now I is confused again.

my radio/transmitter equipment are flysky GT-3B and GR-3E respectively and will handle 4-11v

Flux runs Tekin TX8 ESC
 

HPIguy

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I'm really not sure what you're asking, or what you're confused about? A BEC is always a good idea to prevent a RX brownout caused by pulling more voltage from the ESC's onboard BEC than it can deliver to all components at once. Most onboard ESC based BEC circuits are 3A, and few even deliver that, even though they claim to. I even ran them on my race rigs with much lighter duty servos after a brownout cost me a podium, and some cash out of my wallet from hitting the wall. They're cheap insurance basically.
 

olds97_lss

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I have a Savox 0231MG, it causes a mild brown out on my nitro revo which just has a standard 1600mah NiMH pack in it. To help it, I got a cap (glitch buster) plugged into my receiver to have a bit of reserve power available. Guessing the higher end savox may be even more power hungry.
 

Certified Mike

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The BEC and cap should give you stable power so you can cut down on what you carry. If you're looking for an upgrade, @HPIguy 's comments pretty much have it nailed.
 

HPIguy

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You don't need both a cap and a BEC, as they're doing sort of the same thing, so it's redundant. The difference is, the cap will protect against a very short momentary brown out, but once the cap discharges, you're back to no control. The BEC which actually ties into your power feed and negates the need to power anything from your ESC will keep things running barring something crazy. It frees up your ESC to do the one thing it was designed to do, supply juice to your motor.
 

Certified Mike

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While I'm not sure about the capabilities of the BEC, I am certain that it regulates your voltage. The caps Def protect against Brown out by providing a stored charge, similar to that of a battery pack. Based on just that, yes they are similar but the difference is important when dealing with power hungry servos. Sorry if I was encouraging redundancy. When you're getting ready to purchase, research the technical specs and your questions will be answered.
Good point @HPIguy. :thumbs-up:
 

HPIguy

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As stated, caps provide a very short protection period. The caps sold for RC use are super small, and thus have very little capacity, and are only marketed as glitch busters and not true brownout protection. So claiming they definitely will protect against a brownout is a tough claim to make as there are way too many variables involved to make that claim. Now, if we used bigger caps, it might be a different story. For any PC guys, it's the equivalent to do you plug your nice gaming rig into a surge strip, or buy a UPS? I know which one I'd choose. One other thing to consider is the cap will eat up a channel on your RX as well, and the BEC will not.
 

Certified Mike

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So if I am getting this right, it seems,that the caps would be more in line,for,use with the esc to provide stability and possibly not fry your esc's outputs? Interesting that the caps aren't large enough to provide the juice needed! I guess I would want to experiment with that... But that's me. I actually do have a pretty decent electronics background. I don't know that i'd recommend it for someone who isn't at least somewhat educated in the art of zapping one's self. :hehe:
Thanks for the info @HPIguy. :thumbs-up:
 

HPIguy

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Nope, the caps simply plug into an open channel on your RX to prevent the RX from momentarily losing voltage and causing loss of control. The BEC on the other hand gets wired in directly to your battery plug, and you remove the red wire coming off your ESC's servo plug that goes to your RX. All RX power then comes straight from the BEC, which in turn will power your servos, and anything powered from your RX. Nothing prevents frying your ESC if you connect up a motor that demands more than the ESC can provide. The motor is always the determining factor in any electric setup. Now on a nitro rig where all you're concerned with is powering servos, you don't have to worry about that, BUT; having clean regulated power is always a good thing. On a crawler, and especially scalers with all the lights and accessories, a BEC is a must have item.
 

Certified Mike

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I see... Said the blind man as he picked up his hammer and saw... Or in this case, picked up his hammer and tripped down a flight of stairs! :hehe: Its entirely possible that I would fry the esc, but with a diode and pigy-backing the caps on the power out to the servo direct, out would prevent backfeed to the esc AND provide sufficient power to the servo... Basically doing what I THOUGHT they were supposed to do :hehe:. I guess I understand what the purpose of the caps is but to me, it's kind of like selling hubcaps but claiming they have all the advantage of running true magnesium rims! Wow! Sorry I made you walk me by the hand thru this but I guess I couldn't wrap my head around what I now consider to be almost a total 'fail' in design and purpose. Again, thanks @HPIguy !:thumbs-up:
 

HPIguy

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No problem at all. I wouldn't say they're a total fail, but having used them, they do not completely prevent brownout or glitches. For a few more dollars, a good BEC is damn near bombproof reliability wise.
 

bifft it

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ok so now that the discussion has advanced a bit more I now understand more. I just recieved glitchbusters for my 2 nitro trucks which the savox servos were very glitchy. they take the last channel in my reciever and there would be nomore room for a BEC. Didnt get one for the flux because the savox servo isnt jittery in that truck and really havent noticed it having any issues as i do believe the Tekin RX8 has a built in 6.0vBEC. Upon some research, i notice the BEC that i see are 4v and 6v. whats the point in a high current servo if the servo wont get that required current from the esc?
thats where my confusion came from.
If i understand right. the BEC plugs into the power supply channel of the reciever and the Lipo battery plugs into that ALSO freeing up the 3rd channel since i wont need the glitch buster.
LOL guess i should have been researching new servo sets BEFORE i bought glitch busters for my current servo sets

http://www.skyrc.com/index.php?route=product/product&product_id=154
 
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Certified Mike

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I do understand what you're saying about the motor having too much draw, but doesn't that become a case of ' buy the right esc for the motor/rig you're running'??? I guess just because I have seen how reliable a cap can be on a burdened system (a high powered car audio system is an excellent example), I consider the caps used this way to be pretty much a fail... I'd still like to mess with them some time. It seems to me that it SHOULD work, it's a question of correct components or that they aren't being applied properly. Again, theory on my part at this point.
 

WVNed

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A cap acts as a filter on the power bus and smooths sudden spikes and troughs in the voltage of the bus thereby "busting glitches". It will not fix an underpowered system.
 

HPIguy

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bifft it, Castle BEC systems can be set to output whatever you want using their software. The new 2.0 BEC can be set from 4.75-12V output, with plenty of amperage. And yes, you should absolutely buy the right ESC for your setup, always. But I've seen what happens when people cheap out and don't.
 

bifft it

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guess I will get on the horn tomorrow with Savox, Tekin
I refuse to purchase something from castle that requires something else(castle link) that i will never use again. may as well just light my money on fire as i do not run castle products. 1 electric vehicle. Savage flux. Tekin RX8/T8 that runs perfectly fine
Thread keeps talking about Electric.
WHAT ABOUT NITRO?thats what i run mostly. they dont use an ESC of any sort. My radios will power 4-11v and i will use reciever lipo batteries. I can't imagine a lipo battery fpor a reeciever draining in 20min like my flux does to dual 60C 2s 5000MAH lipos
 

bifft it

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my plan for now will be to run them at 6.0v but at least have all my rc servo needs 7.4v capable.

buy 4-SV1270TG high current servos for all 4 of my vehicles in the steering slot.
move the 2 SC1267 high current that I have into the throttle/brake slot of the 2 nitro trucks i mostly run
and research the 7.4 volt servo gig at a later day

in other words....kickin the can lol
 

Certified Mike

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I would imagine that provides your receiver battery is capable of providing the Colts and amperage required for all your draw, (all the extra lighting, high voltage servos etc) you will be just fine with your nitros! :thumbs-up:
 
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