Strange Current Issue on Matek F765 (3S vs 4S)

Hey All,

I’m trying to get my current sensor more accurate but I’m running into a strange issue.

When running a 3S battery, the current sensor is pretty good. At about 40pc throttle for this setup I get the expected current, around 2A.

However, if I change the battery over to a 4S, the current starts out accurate but as I increase the throttle, the current starts to jump up, at around 40pc I get around 120A, which is obviously not correct. Then it would seem, if I increase this more, the current then starts to come down to a value to one that would be expected?

Any idea what is going wrong here?



I had something similar happen …not on the same board…on a Pixracer…it was the bec providing power to the FC. For some reason it wasn’t working right and browning out the pixracer just enough that the current and voltage sensing system failed. I changed becs and the problem went away.
Not saying it’s the same thing…just similar.

Thanks for the reply, I have a new FC coming tomorrow so hoping that will sort out the issue.


@craigy72 what type of esc are you using and, most importantly, does it have capacitators attached? we‘ve seen a naked multirotor (blheli32) -type esc make that board‘s current sensor go nuts. adding a low ESR-type cap on the input solved the issue.

Its a HAKRC BLHeli_32 Bit 35A - I have attached a capacitor to the main flight controller battery terminal and I also realised that the ground on the ESC was not connected, I only had the telem connected. Seems to be working now. Thanks All!