shawnmc 0 Posted June 3, 2019 This might be a stupid question, but I am a little confused with regards to the current rating on ESC's. I would like to try out the Servonaut T24 rock crawling ESC on the Tamiya bruiser I am building but on the manufactures website it says it's a 20A speed controller. https://www.servonaut.de/shop/en/product_info.php?info=p584_fahrtregler-t24--nachfolger-vom-t20-.html Other cheaper rock crawling ESC are rated much higher 320A etc. What is the meaning of that rating? Can someone specify? Is the Servonaut inferior? Thanks Share this post Link to post Share on other sites
nbTMM 433 Posted June 3, 2019 20Amps is the current rating. About 60-80A would be considered average for an 1/10 scale ESC these days. The higher the current, the more torque/power your motor will make when it is at stall (not turning, or turning very slowly) such as when climbing a rock or steep hill very slowly. Many ESCs like the Tamiya TBLE02S will go into a torque limiting mode when the maximum current is reached (such as when the motor can't turn the wheels because they are jammed by an obstacle), at which point you hear a buzzing or hammering sound coming from the motor, this is to protect the ESC from overload. Cheaper ESCs will simply just try to put out maximum current at all times and if pushed too far, blow up. If you get a beefy ESC you have to be mindful that the motor can't take a huge stall current indefinitely. Too much stall current for too long will make your motor overheat and fail. Looks like you're paying a premium for the Servonaut one for the integration with the Servonaut light and sound modules. They also make a claim about having more steps of speed control, which would give you finer throttle control, especially at low throttle which might be important for crawling. Without actually checking, I would hazard a guess that most half decent (>$80) escs would have fine enough throttle control for crawling anyway. The servonaut also switches at 16kHz so won't make an annoying squealing sound when at partial throttle. Other than those points, the servonaut one doesn't look like anything special to me, seems quite expensive for what it is. Share this post Link to post Share on other sites
shawnmc 0 Posted June 4, 2019 Thanks for the explanation. Wonder why the Servonaut limited their one to 20A when everything else in the market is rated higher? Share this post Link to post Share on other sites
geniusanthony 361 Posted June 4, 2019 Browsed the manual. 20A continuous with 30A (30sec)burst. It appears that the driving style is intended to be different than a typical sport/basher esc valuing realism over absolute power. At 12v 3s voltage levels that equates to 240 watts of power=1/3 hp. It would be interesting to see how it drives though the price definitely turns me off. Share this post Link to post Share on other sites
shawnmc 0 Posted June 6, 2019 I see. Thanks for the info. Share this post Link to post Share on other sites