Originally Posted by
Yosh70
A cap stores energy....nothing more than that. None of my Castle ESC's ever had a cap but my recent Trackstar ESC from HK has one. My thinking is its nothing more than a safeguard.
Now, regarding Castle ESC's, I did have to install caps into the receivers because as everyone knows, earlier Castle's BEC's sucked bigtime.
All of our ESCs have them built in. They are very important to the survival of the ESC, so we don't give customers the option to remove them. In 17.5/21.5 setups it might be okay to remove them from some ESCs because the current is so low and there shouldn't be much ripple, but anything more absolutely needs them if you want the ESC to survive.
Our newer ESC's have a much better BEC. The Mamba X and Mamba Monster X both have an 8 amp BEC and can run digital servos with no issues. I recently used a Monster X BEC to power a 1/5th scale Savox servo in a Losi 5ive-T and had no issues with brownouts on a Spektrum radio. The BEC on the Mamba Max Pro and Mamba Monster were designed before high current digital servos were common and were appropriate at the time.
The only disadvantage to capacitors is that they take up space and add a very slight amount of weight. There is no negative side effects to ESC operation of running input capacitors.
Edit: Just noticed this thread had been bumped from 2015, sorry to quote you and give you a notification from 4 years ago.