Cirtix Stock Club Race - burnt out, pics

[losiracer]

Hi,
I have investigated a problem with my ESC (Cirtix Stock Club Race), whereby it drives the motor only if it initially turned by hand I found two burn chips:


https://plus.google.com/photos/10451...LSH5Yi53IfjnwE

It was driving a 9.5T Ultra Sportsman V2 with 2 Polys supplying power. I believe this is all in spec. Looking at the fails I'm imagining that the 3 power wires each run through two chips. ie the mid two burnt ones run the B wire. As such one of three is down and explains the capacity to run on when hand spun.

My question - so why has this happened. Is there a cause I need to avoid in future.

Cheers, Ian