MMM V3 problem with heatsink

[Pdelcast]

Originally Posted by BrianG

Huh? If the HS does happen to short against the HS, it would definitely matter. You'd be shorting the offending phases together and probably damage the FET(s). I don't think Castle is saying it's ok for the motor connections to touch, they are just saying they could not get the HS to actually short the phases.

But yes, I agree, get rid of those silly plugs and use wires instead. I think they want to use bullets because their CC-Nue motor will have wires with bullets on the end and will offer more of a plug-n-play setup as opposed to soldering anything.

Or maybe use solder-posts (like Mtronics) or thick tabs (like Novak) on the motor outputs instead since they will be smaller in diameter and have much less chance of touching the HS. That way, people wouldn't be soldering directly on the PCB...

Hey Brian,

Well, when you consider that our motors have lower resistance than the heat sink (by about 1/2) -- you can see why the heat sink shorting a phase really isn't an issue. The heat sink actually ablates (burns) away if the bullet manages to get pushed into the heat sink, without damaging the FETs.

One of the tests we do when we stress test our ESCs is to short the output phases during operation -- at low, mid and full throttle. They are designed to survive.