Servo voltage question

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Paultro84

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Arrma RC's
So pretty much every servo has two voltage ratings. Would I need a BEC to get the higher voltage to my servo since the stock ESC isn't adjustable? I have the Savox 1231SG and it's rated at 500oz of torque at 7 or 7.2 volts. I forget the exact number. Anyway, just wondering how to get more volts to it without buying a new ESC that has the option to adjust it.
 
So pretty much every servo has two voltage ratings. Would I need a BEC to get the higher voltage to my servo since the stock ESC isn't adjustable? I have the Savox 1231SG and it's rated at 500oz of torque at 7 or 7.2 volts. I forget the exact number. Anyway, just wondering how to get more volts to it without buying a new ESC that has the option to adjust it.

BEC is the only practical way. Your receiver may not be rated for the increased voltage though.
 
For most servos a Bec is a good idea. But their are a few rare ones that have the same torque at 6 volts as they do at 7.4.
 
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Yep BEC is always a good idea with servos. And it is 7.4V. With a little bit of soldering and work they are an easy install. I used a Castle Creations BEC for mine (wanted waterproofing.) I have a write up somewhere about the servo and BEC I installed recently. Here is just the install of mine.
2458D953-1A38-4741-846E-8D8B5F768A44.jpeg
 
Thanks guys. I'll order one and watch some vids on how to install one.
 
FYI, the Tactic 325 receivers are only rated for 6 volts. The 326 is rated for 8.4v

For only $25 I'll definitely get one. Thank you.

So the voltage being sent to the servo is coming from the receiver and doesn't have anything to do with the ESC? So should I just buy the 326 receiver? Or buy both?
 
For only $25 I'll definitely get one. Thank you.

So the voltage being sent to the servo is coming from the receiver and doesn't have anything to do with the ESC? So should I just buy the 326 receiver? Or buy both?

The receiver is powered by the ESC and the servo is connected to the receiver to get both it's power and signal. When you install the external BEC the receiver and servo get their power from it. The original receiver power from the ESC to the receiver gets disconnected. The ESC fan is still powered from the built in BEC in the ESC. In the old days a separate battery was required to power the receiver and servos, there was no Built in BEC in the ESC's. Hence the BEC being called a "battery eliminator circuit".
Your new external BEC needs to have an input rating sufficient for the voltage of your battery, so if you are using 6s it needs to be 25v. It will connect to the + & - ESC battery wires between the ESC and the battery connector. If your current receiver is a 325 you will need the 326. Or as in this diagram only the servo is powered by the external BEC.
Scaniris_TraxxasSummit_Cablingplan_CCBECtoServov01.jpg
 
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The receiver is powered by the ESC and the servo is connected to the receiver to get both it's power and signal. When you install the external BEC the receiver and servo get their power from it. The original receiver power from the ESC to the receiver gets disconnected. The ESC fan is still powered from the built in BEC in the ESC. In the old days a separate battery was required to power the receiver and servos, there was no Built in BEC in the ESC's. Hence the BEC being called a "battery eliminator circuit".
Your new external BEC needs to have an input rating sufficient for the voltage of your battery, so if you are using 6s it needs to be 25v. It will connect to the + & - ESC battery wires between the ESC and the battery connector. If your current receiver is a 325 you will need the 326. Or as in this diagram only the servo is powered by the external BEC. View attachment 23492

Big thank you for the information and the diagram.
 
What BEC should I get? The only one I'm really finding is the Castle Creations. But it comes set at 6v and you have to buy the castle field link (which cost more than the BEC) to adjust the voltage sent to the servo. I read up on it and I got confused. Haha I think it said you have to plug the field link in to the controller or something. Might have to just forget the whole BEC idea. Haha
 
What BEC should I get? The only one I'm really finding is the Castle Creations. But it comes set at 6v and you have to buy the castle field link (which cost more than the BEC) to adjust the voltage sent to the servo. I read up on it and I got confused. Haha I think it said you have to plug the field link in to the controller or something. Might have to just forget the whole BEC idea. Haha

There are quite a few out there that are adjustable. Not sure what might be the best.
 
What BEC should I get? The only one I'm really finding is the Castle Creations. But it comes set at 6v and you have to buy the castle field link (which cost more than the BEC) to adjust the voltage sent to the servo. I read up on it and I got confused. Haha I think it said you have to plug the field link in to the controller or something. Might have to just forget the whole BEC idea. Haha

This Bec will work just fine. It's programmable up to 9.0 volts which is more than you'll ever need for 8th scale. Usually 6.0 or 7.4. just get the castle link programmer because you'll probably need it in the future if you get another rc and install a new Bec. Go on YouTube for programming it's very simple.

https://www.towerhobbies.com/cgi-bi...d0bIvEElAc6QLLfz7sXQ8KH8a9Hthf9UaAnDhEALw_wcB
 
Hi, Im using @2fast4u connection diagram whit only one input 7.4V battery, CCBEC is set to 7.4V but when going full throtle it variates from 7.4 to 7.25.
I just burn one SW1210SG, but im guessing that voltage variation damaged the servo.
I have also burned another SW1210SG by connecting it directly to 7.4V battery.

8213FA6C-C433-4E0D-A069-BA374249B301.jpeg


Does that BEC voltage variation will damage servos?


https://youtube.com/playlist?list=PLcdKdGBcQ2qFR0pj1EXq6Uv9hfiIdVwir like and subscribe on my youtube channel.

BE3FCF36-13A2-4F5C-9C4C-5ED8C4D29B29.jpeg
 
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The CCBEC can only reduce voltage, so when the voltage of the 2S Lipo drops below 7.4V, the output voltage of the BEC will drop. I would not expect this to damage the servo.

A fully charged 2S Lipo is 8.4V, which is probably why connecting the servo directly to battery damaged it.
 
The CCBEC can only reduce voltage, so when the voltage of the 2S Lipo drops below 7.4V, the output voltage of the BEC will drop. I would not expect this to damage the servo.

A fully charged 2S Lipo is 8.4V, which is probably why connecting the servo directly to battery damaged it.
Thank you!
RX from receiver is 6V
Power from BEC is 7.4v
Is that okay?
Probably I just pushed the servo through the limit…
 
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