3s lipo BEC needed?

[CarLo]

I have a sidewinder and wish to run 3s lipo. I think the 2s lipo wouldn't be enough at 1350mah 25C. 3s would be 1350 mah 30C, more powerful yes. BEC, how to hook it up with sidewinder? Do I need castle link as well?

[irok]

The use of a BEC is really to take the load off your ESC when running 2 servo's or to increase the voltage to your steering servo.

[CarLo]

so i can virtually run 3s lipo with out CC BEC and not worry about burning out any electronics?

[irok]

no,your battery don't matter
what model esc do ya have?...can it handle 3s?
does it have a built in bec?
are you gonna use 2 or more servo's?
do ya wanna run more then 6 volts to your steering servo?
if you do a search on "BEC" you'll find tons of ways to use them for different applications with wiring diagrams

[Rocks R. Good]

It depends on the speed controller. I melted my FXR with 3 cell, I was running one 50lb. micro servo with it.

It has to do with how the BEC works, most adjust current levels sent to the receiver by reducing the voltage through the creation of heat. So the higher your input voltage ( 3 cell vs. 2 cell) the more heat that is created.

With no BEC 3 cell created enough heat to melt my FXR, now with BEC it never goes over it's second heat indicator. This was only with a micro dig servo load, I run my steering off a seperate BEC set to 7.4 volts.

JRH explained it to me that the second form of BEC operated with electronic pulses, and did not create additional heat. BEC's such as Castle and the internal one in Holmes new speed controller operate in this way.

I'm sure I muddied the tech on that, perhaps JRH will chime in.

In my opinion if your going to run 3 cell or higher, run a BEC or the new Torque Master speed controller.

[Arct1k]

I would disagree - the sidewinder has a linear bec which reduces the excess voltage through resistance. As you increase the voltage an load the amount of energy that needs to be scrubbed to reduce to the bec output increases.

This means a lot of heat. For a crawler on 3s I'd always use a switching bec.

[irok]

a 3 cell setup will always build more heat in your esc, an external bec can help take some of the load off and run cooler but if your only running a single servo at 6v and the esc can handle a 3s and already has a built in bec then i still would'nt worry about it,

[JeremyH]

I used to run a 6 cell Nimh on one of my scalers, then I switched to a 3S lipo (same ESC...Sidewinder). I started having troubles with the servo stalling under load. Castle told me this was because of the new battery.

Now, I include an external BEC on EVERY vehicle...

Built in BECs will reduce output to the servos when the motor draws more current.

[CarLo]

Originally Posted by JeremyH

I used to run a 6 cell Nimh on one of my scalers, then I switched to a 3S lipo (same ESC...Sidewinder). I started having troubles with the servo stalling under load. Castle told me this was because of the new battery.

Now, I include an external BEC on EVERY vehicle...

Built in BECs will reduce output to the servos when the motor draws more current.

Thanks! let me know how you wired it,make a diagram. I would like to cop that from you.

[JeremyH]

I wire mine exactly how Caslte Creations recommends:

[C_Money]

Originally Posted by JeremyH

I wire mine exactly how Caslte Creations recommends:

where is the servo in this diagram? I think that would be helpful/

[scottb83]

the sidewinder also has one of the lowest amp internal bec there is. i was told that a 3s 25c lipo was perfect for the sidewinder with 10t cobalt. the castle link is a must id say, i have the sidewinder and cc bec being able to custom program the 2 is great. the castle link adjusts the volts sent to the servo. a bec is a must with high torque servos and high output batteries.

[JeremyH]

Originally Posted by C_Money

where is the servo in this diagram? I think that would be helpful/

Plugged into one of the ports on the Rx. I usually plug in my ESC and servo into the Throttle and Steering ports, then plug the BEC into either the Batt or Aux port.

[C_Money]

and all you need to hook the bec to is the battery leads on the esc? its as easy as that?

[CarLo]

do I need any software CD for the Castle link? it appears to just have USB and that little module to connect to sidewinder ESC.

[vonclod]

ya, but i,m sure you can download it from castle from thier site if you dont know anyone around your area who has one..it should of come with a disc im pretty sure though

[JeremyH]

Originally Posted by C_Money

and all you need to hook the bec to is the battery leads on the esc? its as easy as that?

[CarLo]

Originally Posted by JeremyH

I wire mine exactly how Caslte Creations recommends:

thanks i appreciated it! now, i don't want to manipulate my esc wires. I'm thinking of getting an extension and take that red wire out of the extension so i don't have to mess up my esc.

[JeremyH]

There's not really a need for an extension. The red wire can easily be removed without damage to the ESC. If you look at the connector, there is a small black tab that you can lift and slide out the red wire. I usually just tie it back. It can easily be replaced for future programming of the ESC.

[CarLo]

Originally Posted by JeremyH

There's not really a need for an extension. The red wire can easily be removed without damage to the ESC. If you look at the connector, there is a small black tab that you can lift and slide out the red wire. I usually just tie it back. It can easily be replaced for future programming of the ESC.

o sweet! thanks for the headsup! Man, a lot to learn. I thought being in this hobby for this long, I should know this stuff. But you always learn something new everyday!