HiModel 4s-8s 200 amp esc

[785boats]

There's a few pics here.

http://www.rcgroups.com/forums/showthread.php?t=1274741

Paul.

[ray schrauwen]

I just blew up two of the Himodel 200a 4-8s on 8s!

Both had DP270, etti coolingplate and etti capbank and i did not use the internal BEC.

The first just stopped after one day of racing, the second one blew up on pluginn.

The setup is Delta force 32" knockoff, 8s 5000, NEU 1521 1,5y prop prather 230 speed 58 mph.

The ESC was nice and cool all the time.

I think i might pushed it too far on my setup?

Next time i think i will try the Turnigy marine 240HV.

I keep telling people, they aare only 30Vdc FET's and as soon as someone with really good batts plugs one in, poof!
The only reason others aren't going poof is because batts have some volt drop.

[Lasse Baardseth]

Both my ESC`s had 35v caps.

I dont think that my coolingplate touched the wires because there is two layers of DP270 and two layers of plastidip, but i will take a look when i get home from work.

[bigwaveohs]

I used Plasti-Dip and Arctic Silver epoxy...heatsink is from an electronics surplus store, drilled for the brass tubing.

[Jeff Wohlt]

Do you clean the coating off the fets before the arctic goes on and the plate?

[bigwaveohs]

Look closely at the first photo and you can see where I sanded the FETs level before I applied the Arctic Silver...

[steve-b]

I thought i would shw what i did.
Waterproofed first, i left the original heatsink on and added eight 3/16 brasstubes... 4on the heatsink and 2 on each side.
I will also be adding a cap board later.

[FighterCat57]

Guys, check the thermal conductivity of brass vs aluminum. (the be amazed at copper). Brass ~100, Aluminum ~250, Copper ~400

[Punisher 67]

I have to agree with Ben , copper is extremely good a dissipating heat .

[FighterCat57]

I have to agree with Ben , copper is extremely good a dissipating heat .

It is also extremely heavy and more costly which is why aluminum is used as a light weight inexpensive alternative.

I've discovered an epoxy filler which has the same thermal ranking as aluminum in which I plan to completely encase the ESC with. The key here, the filler is CHEAP. Like $3 a pound. VS Arctic Silver @ $12 per .5 OZ.

In many applications PCB's are encased in epoxy and subjected to extreme environments. Which basically running a PCB under water is considered and extreme condition and should be approached accordingly.

There's another thread in which I've divulged a bit more on (heh, moron) what I plan to test with a batch of these ESC's.

I'll update more on (heh moron) this topic when the parts arrive and testing begins.

[DISAR]

Nice, it's the best way to waterproof escs IMO. Which epoxy filler is that?

[ray schrauwen]

The main problem trying to cool these is that you are drawing heat through the FET to its top rather than from the FET bottom where the heat originates.

My attempt at a disassemble & add cooling plates in between the layers failed. I should not have tried 4 layers of FET boards... oh well...

[ray schrauwen]

Who?

[steve-b]

Maby ill switch to copper tubes. "THE HORROR, THE HORROR"

[FighterCat57]

Maby ill switch to copper tubes. "THE HORROR, THE HORROR"

Honestly, you'll probably be OK with brass as long has you have some cooling and aren't pushing the limits of the specs.