Hi! i had yesterday my first real water test and it did not go as expected, the motor cables ran into the prop and the ESC has now a short circuit in one of the six mosfets (they are actually 12 since it is a 75200)
I wanted to post my experience because I have also had the “that wont happen to me” syndrome and i have learn some things about it:
-The first one and quite clear, fix the cables to the mast properly
-I am quite happy that i have a BMS in my batteries for charge and also discharge, along my build i have seen that sometimes the BMS is only used for charging, i don’t know what would have happened in that case. Do you have experiences?
-I found the the following link very useful to diagnose my ESC before taking it apart: https://solutioncenter.yaskawa.com/search/documents/11185/
On the step 3 I get 0v for the first phase and 0.495v for the other two, in the step 4 i get short circuit on the first phase and open loop in the other two. the rest is fine, also my first phase is toasted.
Here are two photos
of the insides of a Makerbase FS75200 bought in october 2025, it has some improvements against the flipsky inspected here https://www.youtube.com/watch?v=AxnqdFHmr0Q
At least one of the two mosfets in red are short circuited, i may be trying to repair this esc but we will see…
I hope this info is useful for some of you!