mgm24160
 

I got my mgm in. I hooked it up and tried it out. Can some one tell me the cut off on the lipo voltage? I can't seem to find info on it. I thought it was great esc. It seems alot smoother than a bk. Have to give it further testing though.

It cuts Lipo at 3.1v/cell. You can do hard cutoff (stops the motor) or soft cutoff (decreases motor RPM).

I think i missed the cut off setting. Have to go back and look for that. i set it up for 6s and it seemed to draw my cells down farther than wanted. I didn't check them but with the charger when hooked them up. Thanks metal man.

What size daughter board would be Ok?

I am assuming 24 D2Pak7 (4 HI side 4 LO side times 3) 160A FET's per phase with up to 40V (75V later) would be good start.

So, to put all this on "small" PCB would be a fun job, but it would be nice to get dimensions...

As for parts, we can start from simple 24 x IRF2804S-7P and 1 x IR2131S combo.

Artur

The size of the daughterboard doesn't matter too much, as long as it stays smaller than the big schulzes.

Or do the same thing that MGM does.

The controller board in the center and the two powerboards outside (with a heatsink)

How tall can be cube, like MGM?
I can put 2 PCB's with 12 FET's on each (both sides). With 4 FET's I hope we do not need heatsink, it would be heavy enough with all that copper from D2Pak tabs. Or we can add 3d board - 6 FET's - getting expensive ($5.00 each).

Or 2 FET's per phase and heatsink to frame? What if there is no metal frame? Electrical isolation can be done with regular heatpad.

Artur

Personally, I'd use a metal case with small fins, kinda like the Quarks. IMO, shape or size isn't all that important as long as it's not gargantuan. However, a thin, rectangular case would probably be the easiest to mount. Even add some tapped screw holes for small fans. Using a metal case/heatsink, I would definitely use thermal pads like in your link. I've used something like those before and they work well as long as each device is not dissipating tons of heat, which these FETs shouldn't be since they're running in switch mode. This might be a nice kit or upgrade path for a smaller ESC like a 9920 to offer for those who want a high current ESC without the $500+ price - as long as they don't mind the size.

Rethinking the module idea; the brains of an ESC is probably concentrated only on one board. If the whole case is designed so the output FETs are mounted on the outside walls, the processing board might slide vertically in the center so it won't take up much room. Just another option I guess if running an umbilical between two units isn't wanted...