Blue smoking MMM

[Thomas Porfert]

Originally Posted by BrianG

Theory:

Poor connection on the EC5 connector which created resistance. That resistance created a voltage drop when large currents flowed which then caused lots of heat to melt the solder. That same resistance appeared to the ESC as a poor quality battery (high internal R) which increased the amount of ripple currents which stressed the caps too much and heated them up as well.

The blue stuff on the heatsink was from the explosion of an unfortunate nearby Smurf. Sad really, but they should know better.

I agree whole heartily, go with a stronger connector in the future. You need a connector that can actually handle more than 70 amps continuous. The failure of the capacitors is a tail-tale indication of ripple voltage, leading to damage of the capacitors. It may have been related to inadequate batteries; but if you were running 30C+ continuous then it shouldn't have been a problem. It is highly recommended to upgrade to Dean's Ultra Plugs, Traxxas Power Connectors or 5.5mm or 6.6mm bullets; something rated for equal to or more than 70 amps continuous.

We are recommending going with a battery with a 150 amp or higher continuous discharge (IE 5000mAH @ 30C continuous). Anything less could potentially lead to an ESC failure due to ripple voltage. But a strong battery pack is useless without an appropriate connector.

Thomas Porfert
Tech Support
Castle Creations